New Anomalies at Alto Cuilo

Petra Diamonds Ld
27 October 2005



                             Petra Diamonds Limited



             Alto Cuilo - further new magnetic anomalies identified





Petra Diamonds Limited ('Petra' or 'the Company'), the AIM-quoted and ASX-listed
diamond mining group, announces the identification of a new major magnetic
anomaly (148 hectares interpreted surface area) at the Alto Cuilo project in
north eastern Angola and a substantial increase in the number of other known
magnetic anomalies (from 69 to 219).



In July this year a low level Midas helicopter survey was undertaken and Petra
advised that further news would follow when the data from the survey had been
fully processed. The processing and analysis of the data acquired from the Midas
survey is now complete and has resulted in the identification of a major new
anomaly (anomaly 70) which is estimated from the magnetic data acquired from the
Midas survey to be approximately 148 hectares in size and is located
approximately 4 kilometres from the kimberlitic cluster previously announced by
the Company.



Processing of the Midas survey data has also added significantly to the number
of other magnetic anomalies previously identified at Alto Cuilo, with the
original 69 anomalies identified in the previous fixed wing survey now
increasing substantially to 219 from the current Midas survey.



A magnetic image of these anomalies can be viewed at www.petradiamonds.com



Work on the alluvial programme continues with a further three bulk samples
having been processed.  Approximately 2,403 tonnes were treated from these three
bulk samples to recover 237 diamonds totaling 60.30 carats (bottom screen size
of 2mm). The largest stones were 1.87, 1.57 and 1.27 carats. The diamonds
recovered continue to reflect the high gem quality recovered in previous
samples.



Adonis Pouroulis, Petra's Chairman, commented, 'We are delighted to have
discovered a new major magnetic anomaly at Alto Cuilo, again larger in footprint
than the entire 109 hectare (about 115 million tonne) deposit delineated to
date.  Work continues apace at Alto Cuilo, where the combined technical
firepower of Petra and BHP Billiton has successfully uncovered a stream of new
kimberlite anomalies this year.  Alto Cuilo is a project offering exceptional
diamond prospectivity, as also demonstrated by the results of the alluvial bulk
sampling, and we will continue to fast track our development programme.'



 Ends





For further information, please contact:


Parkgreen Communications, London

Justine Howarth / Cathy Malins

Tel [phone]



Petra Diamonds, Perth

John Baillie

Tel [phone]



Field PR, Adelaide

Kevin Skinner

Tel [phone]

Mobile [phone]







Notes to Editors:



In December 2004 Petra implemented a formal Joint Venture Agreement with BHP
Billiton World Exploration Inc ('BHP Billiton') regarding the Alto Cuilo diamond
project in north eastern Angola.  Under the terms of the Joint Venture
Agreement, BHP Billiton can, by investing up to US$60 million in Petra Diamonds
Alto Cuilo Limited, the JV vehicle ('Vehicle') which holds Petra's share in Alto
Cuilo, acquire a share of up to 75% of the Vehicle.



Petra continues to yield exploration success at Alto Cuilo, with the discovery
of several major kimberlitic anomalies in 2005. A low-level Midas helicopter
survey, carried out in July and August this year, identified new anomalies of
26, 60 and 125 hectares in surface area, these discoveries being in addition to
the existing 109 hectares (115 million tonne) deposit identified by Petra in
2004. These four anomalies give an approximate total area of 320 hectares.






                      This information is provided by RNS
            The company news service from the London Stock Exchange                   IE