March 17, 2017

709 Carat Diamond Discovered in Sierra Leone

17 March 2017

AIM: STEL

Stellar Diamonds plc

(“Stellar” or the “Company”)

709 Carat Diamond Discovered in Sierra Leone

Stellar Diamonds plc, the London listed diamond development company focused on West Africa, notes the recent reports regarding the discovery near to Koidu town by an artisanal diamond miner in eastern Sierra Leone of a 709 carat diamond, which has been reported as the 13th largest diamond ever found. Other famous large diamonds discovered in Sierra Leone include the 969 carat “Star of Sierra Leone”, the 770 carat “Woyie River” and the 620 carat “Sefadu”. This latest discovery reaffirms the Company’s belief that Sierra Leone ranks in the very top tier globally for the production of large and high quality diamonds.

Stellar is focussed on the development of its 100% owned Tongo kimberlite diamond project in eastern Sierra Leone, on which it has invested £5.5 million (representing 15p per share) to date defining and growing the current resource and the proposed Tribute Mining agreement between Octea Mining Ltd and Stellar, of the adjacent Tonguma diamond project. Both licences currently have a combined diamond resource of 4.5 million carats.

The economic model for the combined 4.5 million carat diamond resource for the proposed Tongo and Tonguma mine generates a robust estimated attributable post-tax Project NPV (8) and IRR of US$104 million and 31% respectively with estimated projected life of mine revenues of US$1,518 million with diamond grades and prices of 100cpht to 260cpht and US$209 to US$310 per carat respectively. Shareholders should refer to the announcement of 20 February 2017 where details of the proposed tribute agreement are set out.

Review by competent person

This announcement has been reviewed by Karl Smithson, Chief Executive of Stellar, a qualified geologist and Fellow of the Institute of Materials, Metals, Mining, with 28 years’ experience.

This announcement contains inside information for the purposes of Article 7 of EU Regulation 596/2014.

** ENDS **

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

Karl Smithson, CEO

Philip Knowles, CFO

Stellar Diamonds plc

Stellar Diamonds plc

Tel: +44 (0) 20 7010 7686

Tel: +44 (0) 20 7010 7686

Emma Earl

Sandy Jamieson

Cairn Financial Advisers (Nominated Adviser) Tel: +44 (0) 20 7213 0880
Jon Bellis Beaufort Securities Limited (Joint Broker) Tel: +44 (0) 20 7382 8300
Martin Lampshire

Rory Scott

Peterhouse Corporate Finance (Joint Broker)

Mirabaud Securities (Financial Advisers)

Tel: +44 (0) 20 7469 0930

Tel: +44 (0) 20 7878 3360

Lottie Brocklehurst

Charlotte Page

St Brides Partners Ltd

(Financial PR)

Tel: +44 (0) 20 7236 1177

Caution regarding forward looking statements

Certain statements in this announcement, are, or may be deemed to be, forward looking statements. Forward looking statements are identified by their use of terms and phrases such as ”believe”, ”could”, “should” ”envisage”, ”estimate”, ”intend”, ”may”, ”plan”, ”potentially”, ”will” or the negative of those, variations or comparable expressions, including references to assumptions. These forward looking statements are not based on historical facts but rather on the Directors’ current expectations and assumptions regarding the Company’s future growth, results of operations, performance, future capital and other expenditures (including the amount, nature and sources of funding thereof), competitive advantages, business prospects and opportunities. Such forward looking statements reflect the Directors’ current beliefs and assumptions and are based on information currently available to the Directors.

A number of factors could cause actual results to differ materially from the results discussed in the forward looking statements including risks associated with vulnerability to general economic and business conditions, competition, environmental and other regulatory changes, actions by governmental authorities, the availability of capital markets, reliance on key personnel, uninsured and underinsured losses and other factors, many of which are beyond the control of the Company. Although any forward looking statements contained in this announcement are based upon what the Directors believe to be reasonable assumptions, the Company cannot assure investors that actual results will be consistent with such forward looking statements. Accordingly, readers are cautioned not to place undue reliance on forward looking statements. Subject to any continuing obligations under applicable law or any relevant AIM Rule requirements, in providing this information the Company does not undertake any obligation to publicly update or revise any of the forward looking statements or to advise of any change in events, conditions or circumstances on which any such statement is based.

About Stellar Diamonds plc

Stellar is an AIM listed (AIM: STEL) West African focused diamond company with projects at the trial mining and mine development stages in Sierra Leone and Guinea.