18 Apr 2011 07:00
NOT FOR DISTRIBUTION IN THE UNITED STATES OR FOR DISSEMINATION TO US NEWS WIRE SERVICES.
18 April 2011
AIM: STEL
Stellar Diamonds plc
("Stellar" or the "Company")
High Grade Diamond Bulk Sampling Results at Tongo Kimberlite, Sierra Leone
Stellar Diamonds plc, the London listed (AIM:STEL) diamond mining and exploration company focused on West Africa, provides an update on the bulk sampling programme at the Company's 100% owned Tongo kimberlite dyke project in eastern Sierra Leone.
Highlights:
·; 566 tonnes processed for an in-situ grade of 109 cpht
·; 90% of diamonds classified as gem quality
·; Historic diamond valuations indicate Tongo Dyke 1 ore has potential value of over $200/t
·; Sample taken from 70m section of 2,500m total length of Dyke 1
·; 3,000m resource definition drilling programme planned to commence in June
·; Bulk sampling programme continuing using on site processing plant
Karl Smithson, Chief Executive Officer, commented:
"The latest results from bulk sampling of Dyke 1 at Tongo continue to prove highly encouraging. The in-situ grade of the kimberlite remains high at 109 cpht and the diamond quality is excellent. The processing plant is now running at close to optimal capacity and we are now approximately 30% through the sampling programme with 566 tonnes of the planned 2,000 tonnes having been processed".
"Once the surface bulk sampling is completed a 3,000m resource definition drilling programme will be undertaken, after which and subject to results, shaft sinking will commence in preparation for the collection of an underground bulk sample at a depth of 45m. The objective of this aggressive programme is to identify an initial inferred resource statement for Tongo. Based on the high grade and excellent diamond quality so far observed, we believe that Tongo has the potential to deliver substantial value for shareholders".
Tongo Bulk Sampling
Drilling, blasting and extraction of the Dyke 1 bulk sample has continued, with over 1,400 tonnes of material being collected to date from a 70m section of Tongo. Drilling and blasting is being supervised by an experienced and qualified underground diamond miner. The bulk sample is comprised of approximately 60% kimberlite and 40% granite, giving an effective dilution of 40% with the dyke varying in width from 40cm to 100cm. This dilution is a result of having a wide trench width of over 1.1m, in order to provide a safe working environment. In an underground mining scenario, where stope widths will be narrower than this surface trench sampling, the expected dilution would be considerably less. The objective of the bulk sampling programme is to yield 1,000 to 2,000 carats for grade and valuation purposes.
Tongo Processing Plant
The Tongo plant has seen further modifications to improve efficiencies and speed of processing. The plant is running at close to optimal processing conditions of between 5 and 10 tonnes per hour of head feed. Further modifications to the crushing circuit and final recovery are planned in the future to enhance diamond liberation and recovery efficiencies as well as security of the product.
Tongo Bulk Sampling Results
Processing of 566 tonnes of kimberlite and granite combined has resulted in the recovery of 371.45 carats for a diluted diamond grade of 65cpht. Taking into consideration the dilution, the in-situ grade of the kimberlite for the processing to date remains high at 109cpht. Re-crushing of some of the bulk sample remains to be done, which will result in further diamond recovery and an increase in grade for the sample so far processed.
The diamond quality is considered to be excellent, with 90% being classified as gem quality. Some nine stones greater than 1 carat and seven stones over 2 carats have been produced, with the largest diamond to date being 3.15 carats. When a larger diamond parcel has been produced then an export will be undertaken for a valuation to be established for the Tongo Dyke 1 diamonds.
About Stellar Diamonds plc
Stellar is a London (AIM: STEL) listed diamond mining and exploration company that has a portfolio of projects in West Africa.
Stellar owns a 100% interest in four high-grade kimberlite projects that are the focus of exploration and development. In Guinea drilling is resource definition drilling is continuing on the diamondiferous Droujba kimberlite pipe project. In Sierra Leone at the Tongo kimberlite dyke project a bulk sampling programme is ongoing to assess diamond grades and value. At the Kono kimberlite dyke project further bulk sampling is planned on the Company's Lion 5 kimberlite. Bulk sampling is also continuing on the high grade Bouro kimberlite dyke, in Guinea, which is adjacent to the Company's Mandala alluvial diamond mining operation..
For further information please contact the following or visit the Company's website at www.stellar-diamonds.com.
In accordance with the AIM Rules, the information in this announcement has been reviewed by Karl Smithson, CEO of Stellar, a qualified geologist with 22 years' experience.
Stellar Diamonds plc
Karl Smithson, Chief Executive Tel: +44 (0) 7783 707971
Northland Capital Partners Limited
Gavin Burnell, Edward Hutton
Charles Vaughan Tel: +44 (0) 20 7492 4750
Daniel Stewart & Company plc
Martin Lampshire, Oliver Rigby Tel: +44 (0) 20 7776 6550
Pelham Bell Pottinger
Charles Vivian / James MacFarlane Tel: +44 (0) 20 7861 3232