22 Feb 2012 07:00
NOT FOR DISTRIBUTION IN THE UNITED STATES OR FOR DISSEMINATION TO US NEWS WIRE SERVICES.
22 February 2012
AIM: STEL
Stellar Diamonds plc
("Stellar" or the "Company")
Large Diamonds Recovered from Bulk Sampling at Droujba Kimberlite Pipe
Stellar Diamonds plc, the London listed (AIM: STEL) diamond development company focused on West Africa, provides an update on the results of the phase-1 bulk sampling programme at the Company's Droujba kimberlite pipe in Guinea.
Highlights:
·; 268.45 carats recovered to date, including stones of 13.8ct, 6.06ct, 3.75ct and 2.9ct
·; 448t dry tonnes of kimberlite processed to date from two separate samples areas
·; Initial diamond grade of 60 carats per hundred tonnes
·; Reprocessing of tailings likely to increase grade further
·; Further encouraging micro-diamond results received from sampling of kimberlite
·; On track to deliver maiden resource estimate by end of March 2012
Chief Executive Karl Smithson commented:
"The first two bulk sample results are very encouraging, with an initial grade of 60cpht being realised from initial processing, which is consistent with the expectation of high grade.Additionally, the recovery of a number of large stones, including a 13.8 carat and a 6.06 carat stone, from a relatively small parcel of 268 carats of diamonds, suggests a coarse size distribution to the diamond population. Sample processing is progressing well and we expect to have the full results available during March. We remain on track for delivery of the maiden resource statement for the Droujba pipe by the end of March and I look forward to updating shareholders as we progress."
Bulk Sampling and Results
As previously reported, four bulk samples have been collected from a depth of 15m from surface at the base of the previously mined pit on the Droujba pipe. Each sample was accurately measured and the specific gravity and moisture content was carefully determined in order that the dry tonnage could be calculated. These four samples weigh 919 dry tonnes in total and are being processed in batches, with the results of the first two samples shown in the table below.
Sample | Dry Tonnes | Carats Recovered | +1mm dry grade |
DBS-1 | 290.34 | 163.0 | 56.14 |
DBS-2 | 157.67 | 105.45 | 66.88 |
Totals and average grade | 448.01 | 268.45 | 59.92 |
The samples were processed via the Company's 5 tonne per hour DMS plant with diamond recovery being achieved by X-Ray Flowsort and with grease back up in secure conditions and under observation from the Government Mines Monitoring Officer.
Of the 268.45 carats recovered to date, some 27 diamonds are larger than 1 carat, of which 8 are over 2 carats in size. The two largest diamonds weigh 13.8 carats and 6.05 carats. The presence of these large stones suggests a coarse size distribution to the diamond population of the kimberlite sampled to date. Company observation suggests the gem and near gem category comprises approximately 18% and 15% of the recovered diamond population respectively, with rejection and boart stones comprising 66% and 1% respectively. Once the initial processing is completed the tailings will be reprocessed which are likely to liberate more diamonds and hence the grade is likely to also increase. All the diamonds recovered will be exported to Antwerp for acid cleaning, grading and valuation.
Microdiamond Sampling and Results
The microdiamond results of a further two batches of samples, weighing 196.15kg (hypabyssal and kimberlite breccia drill core) and 179.2kg (hypabyssal surface pit samples), have also been received from the Saskatchewan Research Council laboratory in Canada and are reflected in the table below. These results are consistent with previous results in that abundant diamonds have been recovered from the hypabyssal kimberlite including a number of commercial sized stones of greater than 0.85mm in size.
All of these results are now being compiled by independent consultants CAE Mining in order to forecast diamond grade with depth as part of the resource statement process.
RECENT MICRO DIAMOND RESULTS FROM DROUJBA KIMBERLITE | ||||||||||||||||||
Number of Diamonds According to Sieve Size Fraction (mm) | ||||||||||||||||||
Sample | Kimberlite | Sample | +0.075 | +0.106 | +0.150 | +0.212 | +0.300 | +0.425 | +0.600 | +0.850 | +1.180 | +1.700 | +2.36 | Total | Carats | Diamonds | ||
Number | Facies | Weight (kg) | -0.106 | -0.150 | -0.212 | -0.300 | -0.425 | -0.600 | -0.850 | -1.180 | -1.700 | -2.36 | -3.350 | Diamonds | +0.85mm | per kg | ||
GN04-2011-05 | Hypabyssal drill core | 164.70 | 64 | 79 | 50 | 29 | 28 | 8 | 6 | 5 | 1 | 0 | 0 | 270 | 0.0592 | 1.64 | ||
GN04-2011-05 | Kimberlite breccia drill core | 31.45 | 1 | 2 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 5 | 0 | 0.16 | ||
GN04-2011-06 | Hypabyssal surface samples | 179.20 | 130 | 147 | 94 | 57 | 27 | 18 | 10 | 1 | 4 | 1 | 2 | 491 | 0.8450 | 2.74 | ||
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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.
About Stellar Diamonds plc
Stellar is a London (AIM: STEL) listed West African focussed diamond mining and exploration company which is advancing the Droujba kimberlite pipe in Guinea and the Tongo and Kono kimberlite dyke projects in Sierra Leone.
For further information please contact the following or visit the Company's website at www.stellar-diamonds.com.
Stellar Diamonds plc
Karl Smithson, Chief Executive Tel: +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
(Co-Broker)
Martin Lampshire, Antony Legge Tel: +44 (0) 20 7776 6550
Pelham Bell Pottinger
James MacFarlane, Joanna Boon Tel: +44 (0) 20 7861 3232