Assay Results

Griffin Mining Ld 07 October 2002 GRIFFIN MINING LIMITED 1 Berkeley Street, London, W1J 8DJ, United Kingdom Telephone: + 44 (0)20 7016 8821 Facsimile: + 44 (0)20 7016 9124 E mail: griffin@griffinmining.demon.co.uk 7th October 2002 SPECTACULAR ZINC & GOLD ASSAY RESULTS FROM SUMMER DRILLING PROGRAMME AT CAIJIAYING Griffin Mining Limited ('Griffin') has today released the latest assay results calculated from it's 2002 summer diamond drilling programme at Caijiaying. The results exceed all expectations Griffin had for the programme and as previously announced on 16th September 2002 indicates that the resource at Caijiaying is likely to be much larger than previously estimated. The main highlights are: • The results confirm the previously announced visual interpretation of a significant increase in the zinc resource in the part of the deposit drilled. • The results confirm the interpretations which allow the entire resource to be re-modelled for a new larger resource estimate. • The drilling discovered a new lode west of the previously known zone of mineralisation which has recorded the best intersection to date in the deposit of 5m at 36.87% zinc. • On the Southern and Central Sections impressive cumulative thicknesses of mineralisation were encountered, with the Southern Section giving a best cumulative intersection of 32.45m at 12% zinc and the Central Section giving 39.8m at 10.22% zinc. • Some significant gold intercepts were also encountered lower in the drilled zone such as 12m at 4.4g/t gold (using a 1g/t cut-off) including a zone of 5.5m at 7.31g/t Au. • Taken together with earlier gold results, the gold intersections suggest that a distinct part of the overall deposit may have potential as a separate gold resource. The new resource model may throw more light on this aspect. A full report written by independent geological consultants CSA Australia Pty Ltd on the results of the drilling programme are attached hereto. Mladen Ninkov, Chairman, commenting on the activities of Griffin said: 'The results from Caijiaying continually exceed our expectations. These extraordinary assay results confirm our previous visual interpretation and propel us toward a new resource statement from independent resource geologists. We expect that result in November. In addition to the exceptional zinc results the gold results are an added bonus and Griffin will now have to examine the possibility of mining a separate gold resource in addition to our known zinc ore body.' Further information Mladen Ninkov - Chairman Telephone: +44(0)20 7016 8821 Roger Goodwin - Finance Director Telephone: +44(0)20 7016 8821 Charles Dampney - Charles Stanley Telephone: +44(0)20 7739 8200 Griffin Mining Limited's shares are quoted on the Alternative Investment Market (AIM) of the London Stock Exchange (symbol GFM). The Company's news releases are available on the Company's web site: www.griffinmining.com Date; 4-Oct-02 Ref; RC.95.02 The Directors Griffin Mining Ltd 1 Berekeley Street London W1J 8DJ United Kingdom Re: The Caijiaying Project - Drilling Results Dear Sirs, We are pleased to report on the assay results from the recent cross-section drilling program undertaken on the Caijiaying Project between May to August this year. We have previously reported on the interim results and their implications based on visual estimates. I am happy to report that our visual estimates were accurate and in most cases have under-estimated the grade, particularly in medium grade intervals. Thus the general conclusions made in the previous interim report have been confirmed. Drill holes and sampling The drilling program consisted of seven angled core holes drilled on three sections as follows: • a Southern Section comprising two holes, drilled towards the east (ZK315-43 and ZK315-45) on grid line 40020N; • a Central Section (on grid line 40140N) comprising three holes drilled towards the east (ZK315-38, ZK315-39 & ZK315-40) and one hole drilled towards the west to cross-check the other holes (ZK315-42), and • a Northern Section comprising one hole drilled towards the east (ZK315-44) on grid line 40360N). A total of 2031m were drilled. All three sections were designed to assess the geometry of mineralisation intersected in the northern part of the north-south 315 Section previously drilled by the Chinese where 40% of the total resource occurs. The holes were drilled at a 60 degrees angle, orthogonal to the known lodes. The drill program was managed by CSA. The drill core for each hole was logged by a CSA geologist who determined which intervals should be sampled. Each interval was then cut in half by diamond saw, bagged, weighed and packed for air freight to SGS-Analabs of Perth, Western Australia, an internationally accredited independent laboratory. A number of check analyses were conducted on quarter-sawn core samples and a set of blanks and medium and high-grade standard samples were submitted with the batch of samples for analyses. The samples were then subjected to analyses by normal preparation of crushing and grinding to minus 75 microns before a four-acid digest followed by Atomic Absorption Spectrometric analysis to determine zinc, lead and silver. Gold was analyzed by fire assay on a 50g sub-sample of the original. The results of intervals greater than 2m using a 5% zinc cut-off are summarized in the Table 1. Hole-orientation details are also included. In all the holes drilled towards the east the intersections are interpreted to represent an approximate true width of 70% of the actual intersection. In hole ZK315-42 the hole is believed to have been drilled partly down dip. Drill Results On the Southern Section, the recent drilling intersected a new western zone of mineralisation which occurs 15m west of the previously known mineralisation. Both holes intersected this zone. In the first hole (ZK315-43) it consists of a small initial intersection of 2.9m at 6.29% Zn which is followed by an exceptional-grade lode of 5m assaying 36.87% Zn. In the second hole (ZK315-45) which is 15m up dip from the first, the zone is much wider and consists of a better initial intersection of 5.3m at 12.12% Zn followed by a very wide intersection of 16.75m at 13.8%. The intersections lower in these holes are part of the originally known zone and are broadly consistent with the earlier results although thinner. Taken together, the mineralised zone on the southern section is 60m wide with cumulative intersections above the 5% cut off of 12.9m at 19.45% Zn in the first hole and 32.45m at 12% Zn in the second. Previously its width was not known so the new information shows a broad zone of good grade material exists whereas before it was uncertain due to the wrong drilling angle or the early holes. An interesting gold intersection of 4.6m at 3.32g/t Au within the zinc-rich material was also obtained in hole ZK 315-45. Mineralisation in the Central Section (120m to the north of the southern section) also occurs in a 60m wide envelope (also dipping 75 - 80 degrees to the west) but is more abundant, probably due to cross faulting. The vertical extent of the mineralised envelope has been interpreted over 75m. The cumulative intersections in the first two holes drilled towards the east were 39.8m at 10.22% Zn in the upper hole and 28.75m at 7.54% Zn in the lower hole (ZK315-39 drilled 15m down dip of ZK 315-38). The third hole (ZK 315-39) contained much less mineralisation due to an interpreted late cross fault. The hole drilled towards the west (ZK 315-42) is probably at least partly drilled down dip and had a cumulative thickness of 25.55m at 10.75% Zn. It provided essential information to interpret the geometry of the mineralisation. It is worth noting that hole ZK 315-39 also obtained a good gold intersection within the 5% zinc zone of 5.5m at 7.31g/t Au (see Table). In fact the total gold interval is more extensive than this and recorded 12m at 4.14g/t Au (using a 1 g/t Au cut-off). The single drill hole (ZK315-44) on the Northern Section (220m to the north of the Central Section) showed the same general pattern as the Southern Section. It also intersected the new western lode although on this section it is lower grade at 8.65m at 8.3% Zn. However, the hole also intersected a small high-grade intercept between the western and central lodes of 4.4m at 16.33% Zn. Conclusions The main conclusions that can be drawn from these assay results are as follows; • The analyses have confirmed the previously announced interpretations and have generally shown a higher grade than estimated visually. • They have shown that the mineralisation in the northern part of the Zone III deposit is more extensive than previously indicated by the Chinese drilling. • An exceptional grade intercept of 5m at 36.87% Zn was recorded in the newly discovered western lode. This is the best intercept recorded to date in the deposit. • Although mineralisation in the Caijiaying deposit is variable, both the Central and Southern Sections recorded good wide intercepts of cumulative thicknesses of over 30m above 5% Zn within the envelope of mineralisation which is now recognized as being 60m thick. Previously its width was not known. • Two notable gold intersections were recorded, some of which occurs in rocks with no zinc. When taken together with earlier gold results, these intervals are suggesting a pattern which may enable a distinct lower part of the deposit to be modeled as a gold resource. However this would require more sampling to define and would be best done during mining the higher zinc lodes. Work is now underway to combine these latest results into a new geological model in preparation for a revised resource estimate. Signed _______________________ Rupert W. A. Crowe BSc, F.AusIMM, MIAEG Managing Director Table 1. Caijiaying 2002 summary drill-hole results. Hole ZK315-38 Easting 4914.63 Northing 40140.06 RL 1472.417 Dip/Dip Direction -60/090.5 FROM TO INTERVAL Zn% Pb% Ag Au 155.1 159.8 4.7 11.04 1.92 112.34 0.12 incl. 156 159 3 12.47 2.25 121.67 0.16 170.3 176.3 6 9.21 0.46 85.58 0.1 incl. 172.5 175.3 2.8 12.47 0.5 100.54 0.09 185.6 193.9 8.3 14.03 0.5 70.48 0.34 incl. 189.8 193.9 4.1 14.9 0.63 96.1 0.35 198.8 210.5 11.7 10.07 0.71 58.33 0.66 incl. 198.8 205.8 7 11.12 0.96 64.29 0.74 216.2 220.7 4.5 7.43 0.03 2.36 244.9 249.5 4.6 6.9 0.22 20.22 0.24 Cumulative intersections over 2m using a 5% cut-off = 39.8m @ 10.22%Zn Hole ZK315-39 Easting 4896.31 Northing 40139.99 RL 1471.823 Dip/Dip Direction -60/090 FROM TO INTERVAL Zn% Pb% Ag Au 170.4 177.2 6.8 10.25 1.15 84.04 0.13 incl. 174 176.3 2.3 19.79 1.54 126.3 0.06 198.75 205.4 6.65 6.06 0.5 13.23 0.43 221.6 227.5 5.9 7.46 0.15 7.12 0.49 230 235.5 5.5 5.7 0.1 16.82 7.31 240.6 244.5 3.9 8.02 0.07 14.1 1.64 Cumulative intersections over 2m using a 5% cut-off = 28.75m @ 7.54%Zn Hole ZK315-40 Easting 4931.68 Northing 40140.03 RL 1472.194 Dip/Dip Direction -62/092 FROM TO INTERVAL Zn% Pb% Ag Au 153.3 155.8 2.5 7.39 0.54 40 0.14 203 206.1 3.1 5.75 1.43 29.03 1.79 Cumulative intersections over 2m using a 5% cut-off = 5.6m @ 6.48% Hole ZK315-42 Easting 5089.49 Northing 40122.5 RL 1478.091 Dip/Dip Direction -60/270 FROM TO INTERVAL Zn% Pb% Ag Au 173 182 9 7.46 0.83 65 0.32 191.7 198 6.3 14.64 1.16 70.48 0.22 incl. 192.4 196.6 4.2 19.27 1.49 105.71 0.28 200.5 210.75 10.25 11.25 0.81 47.8 0.55 incl. 201 207 6 13.52 0.88 53.33 0.66 Cumulative intersections over 2m using a 5% cut-off = 25.55m @ 10.75m Hole ZK315-43 Easting 4885.34 Northing 40030.05 RL 1472.294 Dip/Dip Direction -60/081 FROM TO INTERVAL Zn% Pb% Ag Au 167.7 170.6 2.9 6.26 0.22 22.41 0.06 186.7 191.7 5 36.87 0.35 82 0.05 194.7 197.7 3 5.69 0.07 0.23 227.5 229.5 2 15.69 0.08 30 0.41 Cumulative intersections over 2m using a 5% cut-off = 12.9m @ 19.45% Hole ZK315-44 Easting 4882.06 Northing 40359.88 RL 1473.662 Dip/Dip Direction -60.5/081 FROM TO INTERVAL Zn% Pb% Ag Au 210.15 218.8 8.65 8.3 1.23 99.51 0.78 230 234.4 4.4 16.33 0.28 21.14 0.16 241.3 244.3 3 9.08 0.13 35 6.09 Cumulative intersections over 2m using a 5% cut-off = 16.05m @ 10.65% Hole ZK315-45 Easting 4899 Northing 40027.08 RL 1473.063 Dip/Dip Direction -60/080 FROM TO INTERVAL Zn% Pb% Ag Au 147.5 156 8.5 9.44 0.46 22.65 0.05 incl. 148.5 153.8 5.3 12.12 0.58 36.32 0.07 160.75 177.5 16.75 13.8 0.52 47.04 0.11 incl. 160.75 175.5 14.75 15.21 0.59 53.42 0.12 184 186.6 2.6 14.92 0.23 72.78 0.08 196.5 201.1 4.6 8.53 0.08 3.32 Cumulative intersections over 2m using a 5% cut-off = 32.45 @ 12.00% Zn This information is provided by RNS The company news service from the London Stock Exchange
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