August 19, 2014

Excellent bulk Sample Grade from Tongo Project, Sierra Leone

19 August 2014


Stellar Diamonds plc

(“Stellar” or the “Company”)

Excellent bulk Sample Grade from Tongo Project, Sierra Leone

Stellar Diamonds plc, the London listed (AIM: STEL) diamond development company focused on West Africa, announces that the final bulk sample grade at its Tongo kimberlite project in Sierra Leone has exceeded 178 carats per hundred tonnes (“cpht”).


  • 1,182 carats recovered from kimberlite ore at an average grade of 178.7cpht
  • Sample grade is 49% higher than the 120cpht applied in current resource estimate
  • 53 diamonds larger than 1 carat, including stones of 6.7 and 4.6 carats
  • Diamonds of excellent shape, colour and clarity with valuation now underway
  • Results expected to increase diamond resource (currently 1.1 million carats)

Stellar Diamonds Chief Executive Karl Smithson commented, “Tongo continues to generate excellent results further underpinning the economic potential of this kimberlite diamond project. We have achieved our objective of collecting a further 1,000 carat parcel for the diamond grade and valuation modelling of Tongo Dyke 1, as part of the ongoing feasibility work. It is highly encouraging to note the substantial increase in grade to 179cpht which has resulted from reprocessing the tailing material. The diamond parcel will now undergo valuation and modelling, with the results expected by early September 2014, prior to a revised financial model and updated resource statement, which we hope to have issued shortly thereafter. We look forward to reporting on these upcoming development milestones as we continue to unlock the intrinsic value of Tongo.”

Dyke-1 Bulk Sampling and Results

All samples collected from Dyke-1 at Tongo have been processed, including second pass tailings material. A total of 1,621t of diluted kimberlite and granite was collected from the bulk sample trench by drilling and blasting in a number of sub-samples termed Sample 7, 8, 9, 10 and 12. These samples were processed in their batches with the DMS plant bottom cut off set at +1.0mm.

Detailed measurement of the sample trench during sample collection has enabled the volume and tonnage of the in-situ kimberlite to be measured. A total of 661.47t of kimberlite has been processed and yielded 1,181.78 carats at an average in-situ +1.0mm grade of 178.7cpht. This is 49% higher than the current resource grade estimate of 120cpht. Grades varied across the sub-samples but all were higher than the resource grade. Sample 10 yielded the highest grade of 305.5cpht and was comprised of highly decomposed kimberlite, resulting in a higher total liberation of diamonds than from fresher kimberlite.

A total of 53 diamonds larger than 1 carat have been recovered, with the two largest stones being 6.7 and 4.6 carats. A large proportion of the goods are of excellent shape, colour and clarity.

Dyke-1Sample Diluted Dry Tons Carats Diluted +1mm Grade (cpht) In-Situ Kimberlite Dry Tons Carats In-Situ Kimberlite +1mm Grade (cpht) Number of Diamonds Diamonds greater than 1-carat
Sample-7 71.37 59.95 84.0 36.37 59.95 164.8 1,001 2
Sample-8 144.45 88.28 61.1 46.04 88.28 191.7 706 5
Sample-9 546.98 382.27 69.9 305.60 382.27 125.1 3,661 17
Sample-10 526.49 481.16 91.4 157.48 481.16 305.5 4,873 20
Sample-12 331.72 170.12 51.3 115.98 170.12 146.7 1,244 9
Totals 1,621.01 1,181.78 72.9 661.47 1,181.78 178.7 11,485 53

Diamond Valuation and Updated Resource Statement

Valuation of the diamond parcel will be undertaken in Antwerp, Belgium. Once the results are received an updated diamond value model will be prepared in September 2014 to generate the expected run of mine diamond value. We will then commission a revised independent resource statement for early October 2014, which we anticipate will show an increase from the current resource estimate of 1.1 million carats.

Ebola Update

The Company notes with concern the escalation of the Ebola virus in West Africa. Since the bulk sampling phase of work is complete and given it is now the height of the rainy season the Company has taken the decision to pause the Tongo work programme and reduce the presence of staff on the project pending results from the current studies. Company personnel who remain are subject to ongoing and stringent daily health checks, controls and restrictions on travel. The Company is also working closely with the local communities and Government representatives to raise awareness within the project area.

About Stellar Diamonds plc

Stellar is an AIM quoted (AIM: STEL) West African focused diamond development company which is advancing its diamondiferous Baoulé kimberlite in Guinea towards trial mining, as well as progressing the 1.1 million carat Tongo Dyke-1 resource in Sierra Leone through a definitive feasibility study. In addition, Stellar holds the 3 million carat Droujba project in Guinea and continues to pursue both diplomatic and legal channels to ensure the proper reinstatement of its Kono licences in Sierra Leone.

** ENDS **

For further information contact the following or visit the Company’s website at

Karl Smithson, CEOPhilip Knowles, CFO Stellar Diamonds plcStellar Diamonds plc Tel: +44 (0) 20 7010 7686Tel: +44 (0) 20 7010 7686
Antony LeggeColin Rowbury Daniel Stewart & Company plc (Nomad)Daniel Stewart & Company plc (Broker) Tel: +44 (0) 20 7776 6550Tel: +44 (0) 20 7776 6550
Hugo de Salis St Brides Media & Finance Ltd Tel: +44 (0) 20 7236 1177
Lottie Brocklehurst St Brides Media & Finance Ltd Tel: +44 (0) 20 7236 1177