12 April 2012

AIM: STEL

Stellar Diamonds plc, the London listed (AIM: STEL) Diamond mining and exploration company focused on West Africa, is pleased to provide final bulk sampling Diamond grades and Diamond values from its Lion-5 kimberlite dyke at its 87km² Kono Diamond licence in eastern Sierra Leone.

Highlights:

• 346 dry tonnes of kimberlite processed to yield 312 carats for in-situ grade of 90cpht
• Diamond value modelled at $220 per carat indicating in-situ kimberlite value of $198 per tonne
• Diamonds of 4.45ct, 3.70ct 3.22ct, 3.07ct, 3.0ct recovered from bulk sampling
• Lion-5 kimberlite mapped over 1,990m with an average width of 1.5m at the bulk sample site
• Resource definition drilling programme planned

Chief Executive Karl Smithson commented:

"The final results from the first phase of evaluation of the Lion-5 kimberlite prove that the body is of both high grade and high Diamond quality. Based on these results, the Company is planning a resource definition drilling campaign over Lion-5, as well as the nearby Pol-K kimberlite, in order to establish a significant maiden resource for the Kono project.

"Over $19m has been invested to date on the Kono licences by Stellar and our former joint venture partners. This has resulted in the systematic exploration of the dyke swarm, including a high resolution geophysical survey and a number of test shafts being sunk to up to 85m depth for bulk sampling. We believe that the Kono project can substantially add to the 3.1 million carat resource base recently established from the Tongo (0.66 million carats) in Sierra Leone and Droujba (2.5 million carats) in Guinea, kimberlite projects, both of which will also be expanded as we continue to grow their respective resources".

"Today we have also announced the uncertainty which has arisen concerning the validity of our Kono licences. I look forward to updating shareholders in the near future".

Lion-5 Bulk Sampling and Processing

As previously reported, the Lion-5 kimberlite has been mapped over a distance of 1,990m to date. The 400 tonne (diluted) bulk sample was collected from a 60m long trench close to the eastern edge of the exploration licence where the dyke had an average width of 1.5m.

A total of 400.59 tonnes of kimberlite/granite have been processed, of which 346.35 tonnes were calculated to be kimberlite. The first pass processing yielded an in-situ grade of 70cpht, however re-crushing and re-processing of the sample tailings has resulted in the liberation of additional diamonds. A total of 312.46 carats have been recovered, resulting in a final increased in-situ grade of 90cpht for the bulk sample.The five largest diamonds weighed 4.45ct, 3.70ct, 3.22ct, 3.07ct and 3.0ct.

The initial results of the processing as reported on 3^rd February 2012 and the final results as reported on the 12^th April 2012 are summarised below:

Diamond Valuation

The first 243.8 carats were recently exported to Antwerp for valuation. Three valuations by independent groups were performed and yielded an average price of $231 per carat. Thereafter, the data of the lowest valuation were submitted to independent Diamond consultant Johannes Ferreira for Diamond price modelling. Based on these data, Diamond price was modelled at between $190 and $245 per carat, with $220 per carat being the best value estimate at this stage. On the basis of the Diamond size distribution model, it is expected that an average of 1 stone in the 45 to 60 carat range and one in the 60 to 150 carat size range may be recovered per 50,000 tonnes of undiluted kimberlite processed.

In accordance with AIM Rules, the information in this announcement has been reviewed by Karl Smithson, Chief Executive of Stellar, a qualified geologist with 23 years' experience.

For further information please contact the following or visit the Company's website at www.stellar-diamonds.com.

Stellar Diamonds plc

Karl Smithson,Chief ExecutiveTel: +44 (0) 20 7257 2930

Northland Capital Partners Limited

(Nominated Advisor and Broker)

Gavin Burnell, Edward Hutton Tel: +44 (0) 20 7796 8800

Daniel Stewart & Company plc

(Joint Broker)

Martin Lampshire, Antony Legge Tel: +44 (0) 20 7776 6550

Pelham Bell Pottinger

James MacFarlane, Joanna Boon Tel: +44 (0) 20 7861 3232