Further Upgrade of JORC Resource at Mpokoto Gold Project
Armadale Capital Plc
Armadale Capital Plc / Index: AIM / Epic: ACP / Sector: Investment
Company
13 October 2014
Armadale Capital Plc (‘Armadale’ or ‘the Company’)
Further
Upgrade of JORC Resource at Mpokoto Gold Project
Armadale, the AIM quoted investment company focused on natural resources
projects in Africa, is pleased to announce a further significant
resource increase and an upgrade in the JORC Code compliant Mineral
Resource estimate (‘MRE’) classification for the Mpokoto Gold Project
(‘Mpokoto’ or the ‘Project’) in the Katanga Province of the Democratic
Republic of Congo. This follows the completion of stage one of an infill
drilling programme carried out in July 2014. Armadale owns an 80%
interest in Mpokoto.
Highlights:
-
Overall Mineral Resources increased by 34% to 678,100 oz gold (‘Au’)
from 506,700 oz Au in total, with 75% of the overall MRE now in
Indicated category (up from 65%)
-
An overall increase of 25% in oxide portion of the Mineral
Resource to 159,000 oz Au from 119,000 oz Au, and the recognition
of higher grade zones in excess of 2g/tonne lying just below
(<20m) the base of the already designed oxide pits
-
The shallower oxide portion of the orebody has been the focus of
the current scoping study given it is nearest to surface (low
strip ratio), very weathered (low treatment cost) and having the
highest recovery (90%) and therefore the lowest cost to produce
-
30% overall increase in transition portion of the resource to
125,000 oz Au from 96,200 oz Au
-
32% overall increase in the fresh, unweathered portion of the
resource to 394,000 oz Au from 299,000 oz Au
-
Indicated Mineral Resources within the oxide zone increased by 138% to
3,600,000 tonnes containing 144,400 oz Au from 1,270,000 tonnes
(60,600 oz Au).
-
Improvement in overall grade to 1.45g/t Au from 1.42g/t Au
-
Significant further upside potential:
-
The deposit remains open along strike and at depth with further
room to define resources between the proposed pits
-
CSA Global Pty Ltd (‘CSA’) have defined a further exploration
target of 1.4Mt to 2.0Mt at 1.2g/t to 1.5g/t Au, for the top 60m
below surface in the immediate surrounding location of the current
resource areas, which will be subject to the second stage of the
infill drilling programme1
-
Defined development strategy to rapidly advance the Project through to
low capex, low opex gold production in H2 2015 – a new pit
optimisation process is underway in addition to an expanded and
updated scoping study due to be published shortly
Justin Lewis, Director of Armadale, said, “The scope and scale of the
Mpokoto Gold Project continues to grow and fuel our confidence that we
will be able to deliver a low capex, low opex commercial gold mining
project in the near future. It is also very gratifying to note the
expansion in the shallow oxide resource, the initial focus of the
group’s development plan, which has now grown by more than 672 per cent
since we acquired the Project.
“This significant 34 per cent increase in the Mineral Resource estimate
to 678,100 oz Au considerably enhances the economics of the entire
asset. Mpokoto offers highly attractive returns and near term production
potential, with robust economics even at low gold prices, and we are
focused on rapidly advancing this Project into production in H2 2015.
The continued unlocking of the Project’s resource potential represents a
major step within this development, and we now remain focused on
completing further value enhancing milestones. This includes the
granting of a mining licence, which is in the final stages, the
expansion of our current scoping study and metallurgical testwork to
improve recovery rates.
“With these initiatives in mind, I expect the remainder of the year to
be highly active in terms of news flow.â€
Summary of changes to the Mineral Resource Estimate
The table below show the changes in the Mineral Resource as a result of
the latest study:
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March 2014 Resource Estimate (according to JORC 2012
Code)
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October 2014 Resource Estimate (according to JORC
2012 Code)
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Percentage Increase between March 2014 and October 2014
|
Inferred & Indicated Resources
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506,700 oz Au
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678,100 oz Au
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33.8%
|
Total tonnage
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11.12 million tonnes
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14.58 million tonnes
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31.1%
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Grade
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1.42 g/t
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1.45 g/t
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2.1%
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Cut-off grade
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0.5 g/t
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0.5 g/t
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-
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Stage One of Reverse Circulation (RC) Drilling Programme
In July 2014 Armadale completed a 2,307m reverse circulation drilling
programme over a total of 46 holes at Mpokoto, the initial results of
which were recently announced. The drilling programme was designed and
conducted with the aim of expanding and upgrading the current JORC
resources and demonstrated that the Project’s mineralisation model is
robust and is proven to be open along strike and at depth in all areas
tested, with significant assays including 20m @ 2.56g/t Au from 14.0m,
14m @ 2.67g/t Au from 31.0m and 4m @ 4.42g/t Au from 56.0m. The drilling
campaign also identified a new zone of continuous mineralisation over a
strike length of approximately 750m to an average depth of 60m down dip.
These results demonstrated the excellent potential for economic
exploitation of the shallow oxide mineralisation and have also supported
the conversion of part of the existing exploration target to a
classified resource.
The drilling specifically aimed to reduce drill hole spacing for a
greater level of confidence and targeted the near-surface potential of
mineralisation. Results of the first stage are incorporated in an
updated Mineral Resource estimate and reported here. Overall there has
been a significant increase in the indicated portion of the MRE, which
now represents 75% of the overall resource. This gives great confidence
in the Mineral Resource of the Project and will underpin the Scoping
Study and further economic assessment of the Mpokoto.
An initial Scoping Study was first completed in April 2014, which
underpinned Mpokoto’s value as a robust gold development project with
attractive economic fundamentals even at a gold price of US$1,100/oz.
Based on this updated Mineral Resource estimation, the Company intends
to run a new pit optimisation and to review, update and expand the
scoping study. Included will be a study of the practicality of
production from a third pit to the south east of pits A and B. Armadale
will also model the transition zone resource tonnes (at higher grade)
presently lying just below the base of the oxide pits. Metallurgical
testwork to improve recoveries from the fresh rock will also be
undertaken (presently 70-73%). An updated scoping study will be
available by the end of October 2014 and will form the basis of a
pre-feasibility study and a maiden reserve for the Project.
Further Information
The MRE is based on the results obtained from 210 drill holes (20,449m),
consisting of 103 reverse circulation holes (‘RC’) totaling 5,892m, and
107 diamond drill holes (including RC holes with diamond core tails)
totaling 14,557m, and is classified as Indicated and Inferred. This is
based on confidence in the geological interpretation and continuity from
the results of the drilling campaign and surface mapping. The results of
the updated estimate are tabulated in Table 1 below. The Mineral
Resource estimates reported in March 2014 are presented in Table 2 and
December 2013 are presented in Table 3 for reference.
Table 1. Mpokoto Mineral Resource, October 2014, by Weathering
|
Weathering
|
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Classification
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Tonnes
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Au g/t
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Ounces
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Oxide
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Measured
|
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-
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-
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-
|
|
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Indicated
|
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3,600,000
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1.25
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144,600
|
|
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Sub-total
|
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-
|
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-
|
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-
|
|
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Inferred
|
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440,000
|
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1.02
|
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14,400
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Total
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4,030,000
|
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1.23
|
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159,000
|
Transitional
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Measured
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-
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-
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-
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Indicated
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2,740,000
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1.26
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110,700
|
|
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Sub-total
|
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-
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-
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-
|
|
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Inferred
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390,000
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1.14
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14,300
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Total
|
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3,130,000
|
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1.24
|
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125,000
|
Fresh
|
|
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Measured
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-
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-
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-
|
|
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Indicated
|
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4,720,000
|
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1.63
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248,000
|
|
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Sub-total
|
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-
|
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-
|
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-
|
|
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Inferred
|
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2,700,000
|
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1.69
|
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146,100
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Total
|
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7,410,000
|
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1.65
|
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394,100
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All
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Grand Total
|
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14,580,000
|
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1.45
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678,100
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Reported from blocks where AU>= 0.5 g/t. Differences in totals may
result due to rounding of raw numbers.
Table 2. Mpokoto Mineral Resource, March 2014, by Weathering
|
Weathering
|
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Classification
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Â
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Tonnes
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Au g/t
|
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Ounces
|
Oxide
|
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Measured
|
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-
|
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|
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-
|
Â
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Â
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-
|
|
|
Indicated
|
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1,270,000
|
Â
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1.49
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60,600
|
|
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Sub-total
|
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1,270,000
|
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1.49
|
Â
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60,600
|
|
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Inferred
|
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1,360,000
|
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1.11
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48,900
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Total
|
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2,630,000
|
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1.30
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Â
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109,500
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Transitional
|
|
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Measured
|
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-
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-
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-
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|
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Indicated
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1,540,000
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1.31
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65,100
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|
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Sub-total
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1,540,000
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1.31
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Â
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65,100
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|
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Inferred
|
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910,000
|
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1.13
|
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33,100
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Total
|
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2,450,000
|
Â
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1.25
|
Â
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98,200
|
Fresh
|
|
|
Measured
|
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-
|
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-
|
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-
|
|
|
Indicated
|
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4,230,000
|
Â
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1.51
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Â
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Â
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205,900
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|
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Sub-total
|
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4,230,000
|
Â
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Â
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1.51
|
Â
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Â
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205,900
|
|
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Inferred
|
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1,800,000
|
Â
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Â
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1.61
|
Â
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Â
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93,100
|
Â
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Â
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Total
|
Â
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Â
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6,040,000
|
Â
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Â
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1.54
|
Â
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Â
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299,000
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All
|
Â
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Grand Total
|
Â
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Â
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11,120,000
|
Â
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Â
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1.42
|
Â
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Â
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506,700
|
Reported from blocks where AU>= 0.5 g/t. Differences in totals may
result due to rounding of raw numbers.
Table 3. Mpokoto Mineral Resource, December 2013, by Weathering
|
Weathering
|
Â
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Classification
|
Â
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Â
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Tonnes
|
Â
|
Â
|
Au g/t
|
Â
|
Â
|
Ounces
|
Oxide
|
Â
|
Â
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Measured
|
Â
|
Â
|
-
|
Â
|
Â
|
-
|
Â
|
Â
|
-
|
|
|
Indicated
|
Â
|
Â
|
250,000
|
Â
|
Â
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1.46
|
Â
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Â
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11,700
|
|
|
Sub-total
|
Â
|
Â
|
250,000
|
Â
|
Â
|
1.46
|
Â
|
Â
|
11,700
|
|
|
Inferred
|
Â
|
Â
|
240,000
|
Â
|
Â
|
1.17
|
Â
|
Â
|
8,900
|
Â
|
Â
|
Total
|
Â
|
Â
|
490,000
|
Â
|
Â
|
1.32
|
Â
|
Â
|
20,600
|
Transitional
|
|
|
Measured
|
Â
|
Â
|
-
|
Â
|
Â
|
-
|
Â
|
Â
|
-
|
|
|
Indicated
|
Â
|
Â
|
870,000
|
Â
|
Â
|
1.50
|
Â
|
Â
|
42,200
|
|
|
Sub-total
|
Â
|
Â
|
870,000
|
Â
|
Â
|
1.50
|
Â
|
Â
|
42,200
|
|
|
Inferred
|
Â
|
Â
|
1,120,000
|
Â
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Â
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1.07
|
Â
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Â
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38,200
|
Â
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Â
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Total
|
Â
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Â
|
1,990,000
|
Â
|
Â
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1.26
|
Â
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Â
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80,400
|
Fresh
|
|
|
Measured
|
Â
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Â
|
-
|
Â
|
Â
|
-
|
Â
|
Â
|
-
|
|
|
Indicated
|
Â
|
Â
|
5,970,000
|
Â
|
Â
|
1.46
|
Â
|
Â
|
280,200
|
|
|
Sub-total
|
Â
|
Â
|
5,970,000
|
Â
|
Â
|
1.46
|
Â
|
Â
|
280,200
|
|
|
Inferred
|
Â
|
Â
|
2,750,000
|
Â
|
Â
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1.46
|
Â
|
Â
|
129,000
|
Â
|
Â
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Total
|
Â
|
Â
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8,720,000
|
Â
|
Â
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1.46
|
Â
|
Â
|
409,200
|
All
|
Â
|
Â
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Grand Total
|
Â
|
Â
|
11,200,000
|
Â
|
Â
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1.42
|
Â
|
Â
|
510,200
|
Reported from blocks where AU>= 0.5 g/t. Differences in totals may
result due to rounding of raw numbers
Current Mineral Resource Estimation (MRE)
The classified mineralisation model is based on drill spacing which was
nominally on 40m sections although the resource model in places
incorporates drilling section lines that are up to 100m apart. This is
justified given the tabular nature of the mineralized horizons.
The deposit has been separated into four areas, defined by intensity of
drilling and changes in strike of mineralisation. The classified Mineral
Resource is confined to Areas 4, 3 and 2 as presented in Figure 1, with
Area 1 lacking sufficient drilling to define a Mineral Resource.
To view Figure 1, which illustrates the mineralisation wireframes,
drilling and AREA definition, please visit the Company's website www.armadalecapitalplc.com
Wireframe solids were generated based on geological interpretations from
CSA, based upon lithological domains and a lower cut-off grade of >=
0.2g/t Au. A north-south fault has been interpreted to offset the
mineralisation across strike between Areas 3 and 4. Depth extents of the
mineralisation model are limited to approximately 50m down dip of the
deepest drill hole intercept, unless drill holes along strike allow the
interpretation to continue at depth without drill support on the current
section. Strike extent of mineralisation is limited to approximately
half the sectional spacing beyond the drill hole limits.
The MRE consists of 20 zones of Au mineralisation and three weathering
domains (oxide, transitional and fresh). Mineralisation domains were
encapsulated by means of 3D wireframed envelopes. Domains were
extrapolated along strike or down plunge to half section spacing or if a
barren hole cut the plunge extension before this limit. Weathering
domains were re-interpreted based upon re-logging of the diamond drill
core in early 2014. The oxide and transitional domains are defined as
zones of variable weathering intensity as described above.
Strike extent of the mineralisation model in Area 4 is approximately
1,000m, plan width of the lenses and intervening waste zones pinches and
swells between 100m and 200m, vertical depth of approximately 200m.
Mineralisation generally outcrops at surface.
The combined strike extent of the mineralisation model in Area 3 is
approximately 650m, plan width of the lens 20m, vertical depth ranges
from 40m to 90m. Mineralisation generally outcrops at surface.
Previous mineralisation potential in Area 2 was targeted in this
programme and successfully raised and incorporated into the classified
resources. Five sub-parallel lenses of mineralisation with a strike
length of about 350m were delineated within 60m from surface.
Grade was interpolated into the block model using ordinary kriging.
Density values of 2.2t/m3 (Oxide zone), 2.65 t/m3
(transitional zone) and 2.73t/m3 (fresh zone) were assigned
to the block model and used to calculate tonnages as reported in Table 1
and Table 2.
Classification of the Mineral Resource estimates was carried out taking
into account the geological understanding of the deposit, QAQC of the
samples, density data and drill hole spacing. The Indicated Mineral
Resources were based upon a higher level of confidence than the Inferred
resources, whereby geological and grade continuity are assumed, but not
confirmed. All available data was assessed and the competent person’s
relative confidence in the data was used to assist in the classification
of the Mineral Resource. The current classification assignment
appropriately reflects the Competent Person’s view of the deposit.
Geology and Mineralisation
Mineralisation occurs in tabular and laterally extensive stratigraphic
horizons within a sedimentary sequence which consists of gold rich
coarse-grained sandstone horizons interlayered with fine to very coarse
layered siliciclastic units overlying metamorphic schistose basement
forming a broad south southwest and west dipping re-folded fold limb,
that was targeted during several drilling programs. The modelling was
constrained within wireframe solids representing the interpreted
geological limits of the gold mineralised sandstone units. The
mineralisation in Area 4 consists of several parallel stacked lenses
that are open down dip.
About Mpokoto Gold Project
Mpokoto is located in the western part of the Katanga Province
approximately 250km west of Kolwezi in the Democratic Republic of Congo,
and approximately 25km from the Zambian border. The area is highly
prospective, with local operators including Ivanhoe Mines and Glencore
Plc. Since 1998, approximately US$20 million has been spent on gold
exploration at the Project.
Competent Person Statement:
The information in this report that relates to Exploration Targets and
Mineral Resources is based on information compiled by Mr David Williams,
a Competent Person, who is a Member of The Australasian Institute of
Mining and Metallurgy. David Williams is employed by CSA Global Pty Ltd,
an independent consulting company. Mr Williams has sufficient experience
which is relevant to the style of mineralisation and type of deposit
under consideration and to the activity which he is undertaking to
qualify as a Competent Person as defined in the 2012 Edition of the
“Australasian Code for Reporting of Exploration Results, Mineral
Resources and Ore Reservesâ€. David Williams consents to the inclusion in
the report of the matters based on his information in the form and
context in which it appears.
Notes
1 The potential quantity and quality mentioned in the
exploration target is conceptual in nature; there has been insufficient
information to estimate a Mineral Resource, and it is uncertain if
further exploration will result in the estimation of a Mineral Resource
at Mpokoto, additional to the Mineral Resource announced in this report.
A copy of the announcement can be found on the Company’s website at www.armadalecapitalplc.com.
Glossary of Technical Terms
Au
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Gold
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3D wireframed envelopes
|
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Computer generated files spatially constraining geological data of
similar affinities.
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Â
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Diamond drill
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A type exploration drilling using a diamond encrusted drill bit,
where a solid stick of rock is extracted from known depths.
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Fresh
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Depth of rock where the original mineralogy of the rock remains
intact, without being affected by chemical or mechanical processes.
|
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Â
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Gravity Separation
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A process in the treatment of ore whereby heavy mineral species such
as gold are separated from the lighter minerals, such as quartz, by
passing the ore through one of a variety of gravity separators.
|
|
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Measured
|
|
|
|
That part of a Mineral Resource for which quantity , grade,
densities, shape and physical characteristics are estimated with
sufficient confidence to support detailed mine planning and final
evaluation of the economic viability of the deposit. A Measured
classification is the highest classification level for Mineral
Resource estimates.
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Â
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Indicated
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That part of a Mineral Resource for which quantity , grade,
densities, shape and physical characteristics are estimated with
sufficient confidence to support mine planning and the evaluation of
the economic viability of the deposit. An Indicated classification
is of a lower confidence level than a Measured classification.
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Â
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Inferred
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That part of a Mineral Resource for which quantity and grade are
estimated on the basis of limited geological evidence and sampling.
An Inferred classification is of a lower confidence level than an
Indicated classification.
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Â
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Metamorphic schistose basement
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Metamorphic rocks (originally altered by high temperatures and
pressures) located at the deepest know depths of geological records,
of a schistose nature.
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Â
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Oxide
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Shallow depth of rock where the original mineralogy of the rock is
extensively broken down by the action of external agencies such as
water percolation and chemical leaching.
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Â
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oz
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Ounce
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QAQC
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Quality Assurance and Quality Control
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Reverse circulation
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A type exploration drilling using a drill bit that hammers and
pulverizes the rock cutting face, and rock chips are then extracted
from known depths.
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Â
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siliciclastic
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Sedimentary rocks built up from rock fragments from pre-existing
rocks, of a siliceous (silica based) mineralogical makeup.
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Â
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Strike
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The direction a geological layer makes as a horizontal line at
surface.
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Â
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Transitional
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Shallow to intermediate depth of rock (generally <150m) where the
original mineralogy of the rock is broken down by the action of
external agencies such as water percolation and chemical leaching.
An intermediate weathering step between oxide and fresh.
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Â
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Weathering
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The process by which rocks are broken down and decomposed by the
action of external agencies such as wind, rain, temperature changes,
plants and bacteria.
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Â
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**ENDS**
Enquiries:
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Â
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Â
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Company
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Justin Lewis, Director
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+61 439 162369
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Charles Zorab
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+44 207 233 1462
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Â
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Nomad and broker: finnCap Limited
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Stuart Andrews/ Christopher Raggett
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+44 207 220 0500
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Â
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Press relations: St Brides Media & Finance Ltd.
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Susie Geliher/Charlotte Heap
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+44 207 236 1177
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Â
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More information can be found on the website www.armadalecapitalplc.com
Notes
Armadale Capital Plc is focussed on investing in and developing a
portfolio of investments, targeting the natural resources sector in
Africa. The Company, led by a team with operational experience and a
strong track record in Africa, has a strategy of identifying high growth
potential businesses where it can take an active role in their
advancement.
Armadale owns an 80% interest in the Mpokoto Gold Project in the
Democratic Republic of Congo. Armadale are focused on proving up the
resource potential of Mpokoto with a view to commencing commercial gold
production.
Armadale also holds approximately a 40% interest in Mine Restoration
Investments Ltd, a South African listed company, which aims to develop
profitable operations within the South African mining industry through
its coal briquetting operation in KwaZulu Natal and acid mine drainage
technology in the Witwatersrand basins.
In addition, Armadale has a small portfolio of listed investments which
are focused on gold and copper production and exploration. The Directors
continue to maintain an active acquisition strategy and will review
investment opportunities that they believe have the potential to be
accretive in terms of shareholder value.
JORC Code, 2012 Edition – Table 1 report template
Section 1 Sampling Techniques and Data
(Criteria in this
section apply to all succeeding sections.)
Criteria
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JORC Code explanation
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Â
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Â
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Commentary
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Sampling techniques
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Â
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Â
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-
Nature and quality of sampling (eg cut channels, random
chips, or specific specialised industry standard measurement
tools appropriate to the minerals under investigation, such as
down hole gamma sondes, or handheld XRF instruments, etc). These
examples should not be taken as limiting the broad meaning of
sampling.
-
Include reference to measures taken to ensure sample
representivity and the appropriate calibration of any
measurement tools or systems used.
-
Aspects of the determination of mineralisation that are
Material to the Public Report.
-
In cases where ‘industry standard’ work has been done this
would be relatively simple (eg ‘reverse circulation drilling was
used to obtain 1 m samples from which 3 kg was pulverised to
produce a 30 g charge for fire assay’). In other cases more
explanation may be required, such as where there is coarse gold
that has inherent sampling problems. Unusual commodities or
mineralisation types (eg submarine nodules) may warrant
disclosure of detailed information.
|
Â
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Â
|
-
The deposit was sampled using both Diamond and Reverse
Circulation (RC) drill holes over four drilling campaigns. Drill
holes were generally drilled 50-100m apart. A total of 107
Diamond holes and 103 RC holes were drilled for a total of
20,449m (14,557m diamond; 5,892m RC). The majority of the holes
were drilled towards the northeast with dips varying between -50
and -60º.
-
RC samples were collected at 1m by riffle splitter. Diamond core
provided Netcom with high quality samples. Appropriate QAQC
protocols were followed, including submission of field
duplicates and insertion of commercial standards
-
Diamond core in ore was NQ size, sampled every 1m in the ore
zone, cut into half, whereas RC samples were obtained by 1m
samples from the rig. Preliminary samples from both Diamond and
RC programmes were crushed and ground to obtain a representative
fraction of greater than 500g. This fraction was then dried to
constant mass at 105ºC. The representative fraction was ground
to 90% passing 100 micron using a laboratory mill. The samples
were weighed. and mixed with a 12:22 Lithium Metaborate/Lithium
Tetraborate Flux containing 4% Lithium Nitrate as an oxidising
agent. The flux/sample mixture was then fused at 1050ºC. All
elements were determined by X-ray Fluorescence Spectrometry
(XRF). LOI was determined gravimetrically in a muffle furnace at
1000ºC.
|
Drilling techniques
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Â
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Â
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-
Drill type (eg core, reverse circulation, open-hole hammer,
rotary air blast, auger, Bangka, sonic, etc) and details (eg
core diameter, triple or standard tube, depth of diamond tails,
face-sampling bit or other type, whether core is oriented and if
so, by what method, etc).
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Â
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Â
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-
Diamond drilling comprises HQ sized core. Drilling involved
coring to the end of hole. Hole depths range from ~0 to 454m.
Core was oriented using single shot orientation tool. RC
drilling comprised a nominal 5 ½ inch diameter face sampling
hammer. Hole depths range from 0m to 150m.
|
Drill sample recovery
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Â
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Â
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-
Method of recording and assessing core and chip sample
recoveries and results assessed.
-
Measures taken to maximise sample recovery and ensure
representative nature of the samples.
-
Whether a relationship exists between sample recovery and
grade and whether sample bias may have occurred due to
preferential loss/gain of fine/coarse material.
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Â
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Â
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-
Diamond core recovery is logged and recorded in the database.
Between 10 to 20% core loss was recorded over parts of the oxide
zone. RC recovery was visually assessed and considered to be
acceptable within the mineralized zones.
-
Diamond core was reconstructed into continuous runs for
orientation marking, depths being checked against the depth
marked on the core blocks. RC samples were visually checked for
recovery, moisture and contamination. A cyclone and splitter
were used to provide a uniform sample and these were routinely
cleaned.
-
Sample Recovery is generally very high within the ore zone. No
significant bias is expected, and any potential bias is not
considered material at this stage of resource development.
|
Logging
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Â
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Â
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-
Whether core and chip samples have been geologically and
geotechnically logged to a level of detail to support
appropriate Mineral Resource estimation, mining studies and
metallurgical studies.
-
Whether logging is qualitative or quantitative in nature.
Core (or costean, channel, etc) photography.
-
The total length and percentage of the relevant intersections
logged.
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Â
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Â
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-
Diamond core and RC drill chips underwent detailed logging
through the entire hole (at 1m intervals for RC chips), with
record kept of colour, lithology, degree of oxidation, water
table etc. Diamond core was geotechnically logged for recovery
and RQD. Information on structure type and orientation are
recorded in the database. Diamond core and RC Chip trays have
been stored in Kasenge site for future reference.
-
Diamond core and RC chip logging included records of lithology,
oxidation state, colour, mineralisation, alteration and veining.
Core was photographed in both dry and wet form.
|
Sub-sampling techniques and sample preparation
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Â
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Â
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-
If core, whether cut or sawn and whether quarter, half or all
core taken.
-
If non-core, whether riffled, tube sampled, rotary split, etc
and whether sampled wet or dry.
-
For all sample types, the nature, quality and appropriateness
of the sample preparation technique.
-
Quality control procedures adopted for all sub-sampling
stages to maximise representivity of samples.
-
Measures taken to ensure that the sampling is representative
of the in situ material collected, including for instance
results for field duplicate/second-half sampling.
-
Whether sample sizes are appropriate to the grain size of the
material being sampled.
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Â
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Â
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-
Diamond core was sawn in half.
-
RC samples were collected on the rig using riffle splitters.
Samples were generally dry.
-
Samples were riffle split to obtain a representative fraction of
>500g.Samples were then dried and ground to 90% passing 100
microns using laboratory mills for XRF analysis.
-
Field QAQC procedures included the insertion of field duplicates
and commercial standards for DD and RC sampling Standards were
inserted at a rate of very 19th and 20th
sample.
-
RC field duplicates were taken from 1m cone split samples at the
rig. Diamond holes were sampled at 1m intervals for raw assays
samples.
-
Sample sizes are considered to be appropriate to accurately
represent the Au mineralisation at Mpokoto based on the
thickness and consistency of the intersections, the sampling
methodology and the percent value assay ranges for the primary
elements.
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Quality of assay data and laboratory tests
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Â
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Â
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-
The nature, quality and appropriateness of the assaying and
laboratory procedures used and whether the technique is
considered partial or total.
-
For geophysical tools, spectrometers, handheld XRF
instruments, etc, the parameters used in determining the
analysis including instrument make and model, reading times,
calibrations factors applied and their derivation, etc.
-
Nature of quality control procedures adopted (eg standards,
blanks, duplicates, external laboratory checks) and whether
acceptable levels of accuracy (ie lack of bias) and precision
have been established.
|
Â
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Â
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-
The gold analysis was done at the ALS laboratory in S.A. by fire
assay which is industry standard for gold. Results provide the
total contained amount of gold in the samples.
-
Not applicable to the project.
-
Field data were all recorded on hardcopies (geological logging,
sampling intervals, etc.) using a set of standard Excel
templates, then manually entered into Excel spreadsheets. Data
were then sent to Mrs. O. Schuh for validation. Assay files were
sent to Mrs. O. Schuh upon receipt from the laboratories.
|
Verification of sampling and assaying
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Â
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Â
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-
The verification of significant intersections by either
independent or alternative company personnel.
-
The use of twinned holes.
-
Documentation of primary data, data entry procedures, data
verification, data storage (physical and electronic) protocols.
-
Discuss any adjustment to assay data.
|
Â
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Â
|
-
Several different company personnel visually verified
intersections in both diamond core and RC chips.
-
No Twinned hole was used during any of the programmes.
-
Field data were all recorded on hardcopies (geological logging,
sampling intervals, etc.) using a set of standard Excel
templates, then manually entered into Excel spreadsheets. Data
were then sent to Mrs. O. Schuh for validation. Assay files were
sent to Mrs. O; Schuh upon receipt from the laboratories.
-
No adjustments were made, other than for values below the assay
detection limit which have been entered as the negative of the
detection limit.
|
Location of data points
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Â
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Â
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-
Accuracy and quality of surveys used to locate drill holes
(collar and down-hole surveys), trenches, mine workings and
other locations used in Mineral Resource estimation.
-
-
Specification of the grid system used.
-
Quality and adequacy of topographic control.
|
Â
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Â
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-
Drill hole collars were surveyed by differential GPS with
horizontal accuracies of about 0.1m. A downhole survey point was
taken every 50m by means of a single shot camera tool by the
drilling contractor.
-
The grid system is WGS_UTM84 Zone 32
-
The topographic surface has been generated from 2m topographic
contours obtained during a topographic survey completed in 2013
by SD Géomatique. All collar locations have been picked up by
means of differential GPS.
|
Data spacing and distribution
|
Â
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Â
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-
Data spacing for reporting of Exploration Results.
-
Whether the data spacing and distribution is sufficient to
establish the degree of geological and grade continuity
appropriate for the Mineral Resource and Ore Reserve estimation
procedure(s) and classifications applied.
-
Whether sample compositing has been applied.
|
Â
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Â
|
-
Drill holes were generally drilled 10-100m apart in the area of
the classified resource.
-
The data spacing and distribution is sufficient to demonstrate
spatial and grade continuity of the mineralised horizon to
support the definition of Inferred and Indicated Mineral
Resources under the 2012 JORC code.
-
No composite have been applied for Diamond and RC drilling.
|
Orientation of data in relation to geological structure
|
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-
Whether the orientation of sampling achieves unbiased
sampling of possible structures and the extent to which this is
known, considering the deposit type.
-
If the relationship between the drilling orientation and the
orientation of key mineralised structures is considered to have
introduced a sampling bias, this should be assessed and reported
if material.
|
Â
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Â
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-
Drilling sections are orientated Northeast - to Southwest with
respect to geographic north. This orientation is perpendicular
to the strike of the host-meta-sediment strata units observed at
Mpokoto. The majority of the drilling is angled to the
Northeast, dipping between -50 and -60º to return mineralisation
intervals with thickness as true as possible. Diamond core
observation confirmed the pertinence of this hole orientation.
-
Diamond drilling confirmed that drilling orientation did not
introduce any bias regarding the orientation of the gold
mineralisation unit.
|
Sample security
|
Â
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Â
|
-
The measures taken to ensure sample security.
|
Â
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Â
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-
Chain of Custody was managed by the various owners of the
project. Samples were stored on site and delivered to the assay
laboratory in Johannesburg by DHL and by transporter Palma sprl
of Lubumbashi (DRC). Samples submission sheets were in place to
track the progress of every batches of samples.
|
Audits or reviews
|
Â
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Â
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-
The results of any audits or reviews of sampling techniques
and data.
|
Â
|
Â
|
-
Sampling techniques are consistent with industry standards.
Consistency of data was validated by Mrs. O; Schuh while loading
into the database (Depth from < Depth to; interval is within
hole depth, check for overlapping samples or intervals, etc.).
Any data which fails the database constraints and cannot be
loaded is returned to field crew for validation, etc.). Global
consistency was also checked later on by plotting sections using
the database and reconciling assays against geology.
|
|
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|
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|
Section 2 Reporting of Exploration Results
(Criteria listed
in the preceding section also apply to this section.)
Criteria
|
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|
Â
|
JORC Code explanation
|
Â
|
Â
|
Commentary
|
Mineral tenement and land tenure status
|
Â
|
Â
|
-
Type, reference name/number, location and ownership including
agreements or material issues with third parties such as joint
ventures, partnerships, overriding royalties, native title
interests, historical sites, wilderness or national park and
environmental settings.
-
The security of the tenure held at the time of reporting
along with any known impediments to obtaining a licence to
operate in the area.
|
Â
|
Â
|
-
The deposit is located in exploration licence PE12897. Armadale
Capital Plc, through its 100% ownership of Kisenge Limited, owns
an 80% interest in the Mpokoto Gold project
-
The tenement is in good standing with no known impediment to
future grant of a mining lease
|
Exploration done by other parties
|
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|
Â
|
-
Acknowledgment and appraisal of exploration by other parties.
|
Â
|
Â
|
-
The tenement has been explored for Au in the past. The project
was established by Cluff Mining Limited in 1998, Goldfields
acquired Kisenge Limited from Cluff Mining in 2003, sold to Casa
in 2007 and to Armadale Capital Plc in 2014.
|
Geology
|
Â
|
Â
|
-
Deposit type, geological setting and style of mineralisation.
|
Â
|
Â
|
-
The Mpokoto gold mineralisation occurs in a stratified
low-metamorpic siliciclastic sedimentary sequence resting on
metamorphosed basement of Proterozoic age. The mineralisation
occurs stratiform and occurs preferentially in coarse-sandy
facies.
|
Drill hole Information
|
Â
|
Â
|
-
A summary of all information material to the understanding of
the exploration results including a tabulation of the following
information for all Material drill holes:
-
easting and northing of the drill hole collar
-
elevation or RL (Reduced Level – elevation above sea
level in metres) of the drill hole collar
-
dip and azimuth of the hole
-
down hole length and interception depth
-
hole length.
-
If the exclusion of this information is justified on the
basis that the information is not Material and this exclusion
does not detract from the understanding of the report, the
Competent Person should clearly explain why this is the case.
|
Â
|
Â
|
-
This material has been adequately reported in previous
announcements.
|
Data aggregation methods
|
Â
|
Â
|
-
In reporting Exploration Results, weighting averaging
techniques, maximum and/or minimum grade truncations (eg cutting
of high grades) and cut-off grades are usually Material and
should be stated.
-
Where aggregate intercepts incorporate short lengths of high
grade results and longer lengths of low grade results, the
procedure used for such aggregation should be stated and some
typical examples of such aggregations should be shown in detail.
-
The assumptions used for any reporting of metal equivalent
values should be clearly stated.
|
Â
|
Â
|
-
Not reporting exploration results.
-
Not applicable
-
Not applicable
|
Relationship between mineralisation widths and intercept lengths
|
Â
|
Â
|
-
These relationships are particularly important in the
reporting of Exploration Results.
-
If the geometry of the mineralisation with respect to the
drill hole angle is known, its nature should be reported.
-
If it is not known and only the down hole lengths are
reported, there should be a clear statement to this effect (eg
‘down hole length, true width not known’).
|
Â
|
Â
|
-
Drill hole angles of between -50â° and -60â° toward the northeast
are adequate to drill the moderately dipping to south west units.
-
Not reporting exploration results.
-
Not reporting exploration results.
|
Diagrams
|
Â
|
Â
|
-
Appropriate maps and sections (with scales) and tabulations
of intercepts should be included for any significant discovery
being reported These should include, but not be limited to a
plan view of drill hole collar locations and appropriate
sectional views.
|
Â
|
Â
|
-
Refer to diagrams in body of text
|
Balanced reporting
|
Â
|
Â
|
-
Where comprehensive reporting of all Exploration Results is
not practicable, representative reporting of both low and high
grades and/or widths should be practiced to avoid misleading
reporting of Exploration Results.
|
Â
|
Â
|
-
Not reporting exploration results.
|
Other substantive exploration data
|
Â
|
Â
|
-
Other exploration data, if meaningful and material, should be
reported including (but not limited to): geological
observations; geophysical survey results; geochemical survey
results; bulk samples – size and method of treatment;
metallurgical test results; bulk density, groundwater,
geotechnical and rock characteristics; potential deleterious or
contaminating substances.
|
Â
|
Â
|
-
Surface sampling and mapping were completed over different field
campaigns by Cluff, Goldfields and CASA. Jigsaw Geoscience was
contracted to complete detailed mapping of the project. An
aeromagnetic survey of the project was completed in 2005 giving
further insight over the geometry of deformed host units.
|
Further work
|
Â
|
Â
|
-
The nature and scale of planned further work (eg tests for
lateral extensions or depth extensions or large-scale step-out
drilling).
-
Diagrams clearly highlighting the areas of possible
extensions, including the main geological interpretations and
future drilling areas, provided this information is not
commercially sensitive.
|
Â
|
Â
|
-
Metallurgical test work will be completed on recently drilled
resource area. Some more DD drilling is planned in untested
areas to upgrade the resource, reduce spacing and test
mineralisation extensions.
-
Refer to diagrams in body of text
|
|
Â
|
Â
|
|
Â
|
Â
|
|
Section 3 Estimation and Reporting of Mineral Resources
(Criteria
listed in section 1, and where relevant in section 2, also apply to this
section.)
Criteria
|
Â
|
Â
|
JORC Code explanation
|
Â
|
Â
|
Commentary
|
Database integrity
|
Â
|
Â
|
-
Measures taken to ensure that data has not been corrupted by,
for example, transcription or keying errors, between its initial
collection and its use for Mineral Resource estimation purposes.
-
Data validation procedures used.
|
Â
|
Â
|
-
Data used in the Mineral Resource estimate is sourced from a
data base dump, provided in the form of an MS Access database.
Relevant tables from the data base are exported to MS Excel
format and converted to csv format for import into Datamine
Studio 3 software for use in the Mineral Resource estimate.
Validation protocols for the data entered to the Data Shed
database are described in Section 1.
-
Datamine has inbuilt and operator coded drill hole validation
features that test for overlapping sample intervals, differences
between collar elevations and the adjacent DTM elevation, down
hole survey readings with significant deviations over nominated
down hole intervals. Drill holes were loaded into 3D space and
visually checked for any obvious errors in survey measurements.
|
Site visits
|
Â
|
Â
|
-
Comment on any site visits undertaken by the Competent Person
and the outcome of those visits.
-
If no site visits have been undertaken indicate why this is
the case.
|
Â
|
Â
|
-
-
A CSA representative of the Competent Person (CP) visited site
on several occasions prior to this resource estimation. The CP’s
representative has extensive experience in sediment-hosted and
orogenic gold deposits and has a strong structural background to
be able to evaluate and interpret the deposit geology and
mineralisation data based on his experience. The CP’s
representative inspected geological exposure, drill sites,
logging and sampling procedures and site security and general
surroundings, and found all to be satisfactory and of adequate
quality to support the Mineral Resource estimate.
|
Geological interpretation
|
Â
|
Â
|
-
Confidence in (or conversely, the uncertainty of ) the
geological interpretation of the mineral deposit.
-
Nature of the data used and of any assumptions made.
-
The effect, if any, of alternative interpretations on Mineral
Resource estimation.
-
The use of geology in guiding and controlling Mineral
Resource estimation.
-
The factors affecting continuity both of grade and geology.
|
Â
|
Â
|
-
A geological model was constructed based upon measured and
observed structural and lithological data. The Competent Person
has high confidence in the geological interpretation supporting
the Mineral Resource.
-
46 RC holes were drilled in 2014, to complement the pre-existing
77 RC holes
-
21 diamond drill holes were completed in the past two years to
complement the pre-existing 63 diamond holes.
-
Drill hole logs, samples and assays, plus surface geological
outcrop mapping form the basis of the geological interpretation.
-
Previous Mineral Resource estimates (x2) were based upon
geological interpretations with much less underlying geological
factual support. The interpretations generally used the same
strike and dips for the geological models as the current Mineral
Resource model.
-
Lithological logs of the conglomerates hosting the
mineralisation controlled the widths and extents of the
mineralisation envelopes.
-
Mineralisation occurs in tabular and laterally extensive
stratigraphic horizons. A north-south fault has been observed in
drill core and outcrop cutting the mineralisation along strike
between Areas 3 and 4. Depth extents of the mineralisation model
are limited to approximately 50m down dip of the deepest
drillhole intercept, unless drill holes along strike allow the
interpretation to continue at depth without drill support on the
current section. Strike extent of mineralisation is limited to
approximately half the sectional spacing beyond the drill hole
limits.
|
Dimensions
|
Â
|
Â
|
-
The extent and variability of the Mineral Resource expressed
as length (along strike or otherwise), plan width, and depth
below surface to the upper and lower limits of the Mineral
Resource.
|
Â
|
Â
|
-
Strike extent of the mineralisation model in Area 4 is
approximately 1,000m, plan width of the lenses and intervening
waste zones pinches and swells between 100m and 200m, vertical
depth of approximately 200m. Mineralisation generally outcrops
at surface.
-
Strike extent of the mineralisation model in Area 3 is
approximately 650m, plan width of the lens 20m, vertical depth
ranges from 40m to 90m. Mineralisation generally outcrops at
surface.
-
Strike extent of the mineralisation model in Area 2 is
approximately 350m, plan width of the lens 30 m, vertical depth
to 200 m. Mineralisation generally outcrops at surface.
|
Estimation and modelling techniques
|
Â
|
Â
|
-
The nature and appropriateness of the estimation technique(s)
applied and key assumptions, including treatment of extreme
grade values, domaining, interpolation parameters and maximum
distance of extrapolation from data points. If a computer
assisted estimation method was chosen include a description of
computer software and parameters used.
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The availability of check estimates, previous estimates
and/or mine production records and whether the Mineral Resource
estimate takes appropriate account of such data.
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The assumptions made regarding recovery of by-products.
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Estimation of deleterious elements or other non-grade
variables of economic significance (eg sulphur for acid mine
drainage characterisation).
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In the case of block model interpolation, the block size in
relation to the average sample spacing and the search employed.
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Any assumptions behind modelling of selective mining units.
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Any assumptions about correlation between variables.
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Description of how the geological interpretation was used to
control the resource estimates.
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Discussion of basis for using or not using grade cutting or
capping.
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The process of validation, the checking process used, the
comparison of model data to drill hole data, and use of
reconciliation data if available.
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CAE Studio 3 (Datamine) software was used for all geological
modelling, block modelling, grade interpolation, MRE
classification and reporting. GeoAccess Professional and Snowden
Supervisor were used for geostatistical analyses of data. The Au
interpretation was based upon a lower cut-off of 0.2g/t Au and a
lithological envelope (conglomerates). The MRE consists of 20
zones of Au mineralisation and two weathering domains (oxide and
fresh). Mineralisation domains were encapsulated by means of 3D
wireframed envelopes. Domains were extrapolated along strike or
down plunge to half a section spacing or if a barren hole cut
the plunge extension before this limit.
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Top cuts were used to constrain extreme grade values. A top cut
was set to 20g/t. All samples in Area 2 and 4 were composited to
1m intervals, whilst drill hole data in Area 3 were composited
to 2m intervals, based upon raw drill hole sample lengths. All
drill hole data (RC and Diamond) were utilised in the grade
interpolation.
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A block model was constructed using all mineralisation domains
and weathering profiles, capped by a topographical DTM. Block
sizes of 20m (X) by 20m (Y) by 10m (Z) were selected based upon
typical drill hole spacing (40m along strike). The model was not
rotated.
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Grade estimation was by Ordinary Kriging (OK) with Inverse
Distance Squared (IDS) estimation concurrently run as a check
estimate. A minimum of 12 and maximum of 40 samples were used in
any one block estimate. A maximum of 4 composited samples per
drill hole were used in any one block estimate. Cell
Discretisation of 5 x 5 x 5 was used. Grade interpolation was
run within the individual mineralisation domains, acting as hard
boundaries. Weathering profiles were used as soft boundaries and
did not control grade interpolation.
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The grade model was validated by 1) creating slices of the model
and comparing to drill holes on the same slice; 2) swath plots
comparing average block grades with average sample grades on
nominated easting, northing and RL slices; and 3) mean grades
per domain for estimated blocks and flagged drill hole samples.
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The current Mineral Resource was checked against the previously
reported Mineral Resources and shown to be of an increased
tonnage but similar grade.
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No by products were modelled.
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No selective mining units were assumed in this model.
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Only Au was modelled therefore no correlation between other
variables was required.
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Moisture
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Whether the tonnages are estimated on a dry basis or with
natural moisture, and the method of determination of the
moisture content.
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Tonnages are estimated on a dry basis.
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Cut-off parameters
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The basis of the adopted cut-off grade(s) or quality
parameters applied.
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The reporting cut-off grade of 0.5g/t was selected due to it
being the same cut-off used to report previous Mineral Resources.
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Mining factors or assumptions
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Assumptions made regarding possible mining methods, minimum
mining dimensions and internal (or, if applicable, external)
mining dilution. It is always necessary as part of the process
of determining reasonable prospects for eventual economic
extraction to consider potential mining methods, but the
assumptions made regarding mining methods and parameters when
estimating Mineral Resources may not always be rigorous. Where
this is the case, this should be reported with an explanation of
the basis of the mining assumptions made.
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It is assumed the deposit, if mined, will be developed using
open pit mining methods. No assumptions have been made to date
regarding minimum mining widths or dilution.
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Metallurgical factors or assumptions
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The basis for assumptions or predictions regarding
metallurgical amenability. It is always necessary as part of the
process of determining reasonable prospects for eventual
economic extraction to consider potential metallurgical methods,
but the assumptions regarding metallurgical treatment processes
and parameters made when reporting Mineral Resources may not
always be rigorous. Where this is the case, this should be
reported with an explanation of the basis of the metallurgical
assumptions made.
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Metallurgical test work since 2010 suggest the oxide
mineralisation is amenable to cyanidation with good gold
recoveries on CIL bottle roll tests. Recent test work has
indicated heap leach as a potential processing route for
achieving acceptable gold recoveries of up to 86%.
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Metallurgical test work since 2010 suggest the transition zone
mineralisation is amenable to cyanidation with reasonable gold
recoveries on CIL bottle roll tests. Recent test work has
indicated heap leach as a potential processing route for
achieving acceptable gold recoveries of up to 60%.
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Sulphide mineralisation metallurgical test work has suggested
that CIL gold recoveries are at 51%. It has been recommended by
previous workers that a heap leach based processing flowsheet
with an appropriate sulphide mineralisation pre-treatment method
(such as bio-heap leach) may be a processing method.
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No detailed metallurgical test work has been completed to date
on the project.
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Environmental factors or assumptions
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Assumptions made regarding possible waste and process residue
disposal options. It is always necessary as part of the process
of determining reasonable prospects for eventual economic
extraction to consider the potential environmental impacts of
the mining and processing operation. While at this stage the
determination of potential environmental impacts, particularly
for a greenfields project, may not always be well advanced, the
status of early consideration of these potential environmental
impacts should be reported. Where these aspects have not been
considered this should be reported with an explanation of the
environmental assumptions made.
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No environmental baseline studies have been completed to date on
this project.
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The project area’s topography consists of gentle hills and
valleys, with elevation ranging between 900m and 1200m.
Vegetation is mainly indigenous savannah, open woodland,
grassland plains and minor agricultural plots. Several rivers
flow through the project area.
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The climate in the project’s region is tropical to sub-tropical
with an annual rainfall of up to 1500mm.
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The topography around the Mpokoto deposit has space for
potential tailings storage areas, waste disposal, heap leach
pads and processing plants.
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Bulk density
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Whether assumed or determined. If assumed, the basis for the
assumptions. If determined, the method used, whether wet or dry,
the frequency of the measurements, the nature, size and
representativeness of the samples.
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The bulk density for bulk material must have been measured by
methods that adequately account for void spaces (vugs, porosity,
etc), moisture and differences between rock and alteration zones
within the deposit.
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Discuss assumptions for bulk density estimates used in the
evaluation process of the different materials.
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Density measurements were taken from diamond drill core, for
which there are no detailed records regarding method of
measurement. It is assumed the measurements were taken using
conventional wet immersion techniques (weight in air, weight in
water). No information available regarding any coating of core
prior to immersion.
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Density values were added to drill hole file and statistical
analyses conducted based upon weathering profiles. Density
values of 2.2t/m3 (Oxide zone), 2.65 t/m3 (transitional zone)
and 2.73t/m3 (fresh zone) were assigned to the block model and
used to calculate tonnages.
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Classification
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The basis for the classification of the Mineral Resources
into varying confidence categories.
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Whether appropriate account has been taken of all relevant
factors (ie relative confidence in tonnage/grade estimations,
reliability of input data, confidence in continuity of geology
and metal values, quality, quantity and distribution of the
data).
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Whether the result appropriately reflects the Competent
Person’s view of the deposit.
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Classification of the Mineral Resource estimates was carried out
taking into account the geological understanding of the deposit,
QAQC of the samples, density data and drill hole spacing. The
Indicated Mineral Resources were based upon a higher level of
confidence than the Inferred resources, whereby geological and
grade continuity are assumed, but not confirmed.
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All available data was assessed and the competent persons
relative confidence in the data was used to assist in the
classification of the Mineral Resource.
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The current classification assignment appropriately reflects the
Competent Person’s view of the deposit.
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Audits or reviews
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The results of any audits or reviews of Mineral Resource
estimates.
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No audits or review of the Mineral Resource has been carried out
to this time.
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Discussion of relative accuracy/ confidence
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Where appropriate a statement of the relative accuracy and
confidence level in the Mineral Resource estimate using an
approach or procedure deemed appropriate by the Competent
Person. For example, the application of statistical or
geostatistical procedures to quantify the relative accuracy of
the resource within stated confidence limits, or, if such an
approach is not deemed appropriate, a qualitative discussion of
the factors that could affect the relative accuracy and
confidence of the estimate.
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The statement should specify whether it relates to global or
local estimates, and, if local, state the relevant tonnages,
which should be relevant to technical and economic evaluation.
Documentation should include assumptions made and the procedures
used.
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These statements of relative accuracy and confidence of the
estimate should be compared with production data, where
available.
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An inverse distance estimation algorithm was used in parallel
with the ordinary Kriged interpolation, with results very
similar to the Kriged results.
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No other estimation method or geostatistical analysis has been
performed.
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The Mineral Resource is a local estimate, whereby the drill hole
data was geologically domained above a nominated Au cut-off
grade, resulting in fewer drill hole samples to interpolate the
block model than the complete drill hole dataset, which would
comprise a global estimate.
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Relevant tonnages and grade above a nominated cut-off grade are
provided in the introduction and body of this report. Tonnages
were calculated by filtering all blocks above the cut-off grade
and sub-setting the resultant data into bins for weathering and
classification. The volumes of all the collated blocks were
multiplied by the dry density value to derive the tonnages. The
gold metal value (g) for each block was calculated by
multiplying the Au grade (g/t) by the block tonnage. The total
sum of all metal (g) for the deposit for the filtered blocks was
divided by the total tonnage to derive the reportable Au grade
(g/t).
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No production data is available to reconcile results with.
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