Botswana Update

Petra Diamonds Ld
16 May 2007


For release 16 May 2007

                             Petra Diamonds Limited

                         Exploration Update - Botswana


Petra Diamonds Limited ('Petra' or 'the Company'), the AIM-quoted diamond mining
group, announces an update with regards to the exploration programme in
Botswana.


Highlights

  • Drilling results from the 600 metre diameter gravity negative anomaly
    (previously reported by Petra)  confirm that the surface area of the
    diamondiferous kimberlite within the anomaly is likely to be significantly
    larger than previously accepted

  • A new kimberlite (X25) has been identified within Petra's licence areas -
    this discovery is highly significant as the area has been explored
    thoroughly by other exploration companies in the past, yet new technologies
    and methodologies employed by Petra have now led to this important discovery

  • Petra has acquired new prospecting licences in the Jwaneng area - these
    new licences hold two known diamondiferous kimberlites (DK4 and DK6)

  • 20 highly encouraging targets have been identified in Petra's Orapa North
    licence block



Drilling at large gravity anomaly

The 600 metre diameter gravity negative anomaly (reported on in Petra's
quarterly report to 31 December 2006) has now been drill-tested. Two
strategically placed holes (relative to the gravity anomaly) both intersected
kimberlite beneath approximately 40 metres of Kalahari sand cover. Geophysical
modeling suggests the body, previously described as inconclusive (and small) in
terms of size, is likely to be 'champagne' glass shaped with a surface area
(interpreted from geophysics) of approximately 25 hectares. The target is also
potentially much larger than previously believed. Material for the above two
holes has been submitted to Petra's Helam laboratory and indicator minerals
recovered from the samples will be probed by an outside facility for diamond
bearing prospectivity. This kimberlite has the potential to be a substantial
deposit, although the grade over the majority of it is at this time untested.



Kimberlite X25

The ground follow up on the 700km(2) low-level Xcalibur horizontal gradient
magnetic survey previously flown by Petra has resulted in the discovery of a new
kimberlite, X25. The area in the vicinity of this kimberlite has been
intensively explored by reputable exploration companies since the early 1980's,
but new technologies are now available enabling Petra to successfully deploy an
Xcalibur high resolution gradient magnetic survey. Targeting a magnetic anomaly
picked from the Xcalibur dataset, a drilling campaign resulted in the discovery
of the X25 kimberlite. Kimberlite was intersected from 79 metres to a depth of
125 metres; initial geophysical interpretation suggests a smaller kimberlite. In
the light of this significant discovery, more exploration work is being planned
for the locality, although no further work will be carried out on this
kimberlite due to its small size.



Jwaneng Licences

Petra has recently been granted prospecting licences in the vicinity of the
Jwaneng diamond mine. These licence areas hold two previously identified
kimberlites, DK4 and DK6, both of which are diamondiferous. Petra will undertake
further work to ascertain the prospectivity of these kimberlites as well as put
together a work programme to explore these new licence areas.



Xcalibur survey

A large 12,673 line kilometre high resolution magnetic gradiometer Xcalibur
survey has been successfully completed over the Orapa North sections of Petra's
licence areas. This approach, which entails collecting data at a flight height
of 20 metres, is able to detect kimberlites with enough detail to allow for
drilling without geophysical ground follow-up. Interpretation of the data
received has resulted in a minimum of twenty high priority targets that require
further investigation.



Ends


Notes

1. The information in this update that relates to Exploration Results, Mineral
Resources or Ore Reserves is based on information compiled by Jim Davidson, Pr.
Sci Nat (reg No 400031/06), who is a Member of the Geological Society of South
Africa, a 'Recognised Overseas Professional Organisation' ('ROPO'), included in
a list promulgated by the ASX from time to time. Jim Davidson is a full-time
employee of the Company and 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 2004 Edition of the 'Australasian Code for Reporting of Exploration Results,
Mineral Resources and Ore Reserves'. Jim Davidson has given his written consent
to the inclusion in this announcement of the matters based on his information in
the form and context in which it appears. Jim Davidson is the Qualified Person
for the purposes of the AIM Guidance Note on Mining, Oil and Gas Companies dated
March 2006


2. It should be noted that the potential quantity in this report is conceptual
in nature, there has been insufficient exploration to define a Mineral Resource
and it is uncertain if further exploration will result in the determination of a
Mineral Resource.



For further information, please contact:


Cathy Malins / Annabel Leather               Telephone: [phone]

Parkgreen Communications, London


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