African Mining Network

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AMN - GUINEA: 55ct diamond recovered from Baoulé

Stellar Diamonds, the London-listed diamond development company focused on West Africa, has issued an update on trial mining operations at its 75%-owned, 5 hectare Baoulé kimberlite pipe in Guinea.

Highlights:

-          55 ct diamond recovered confirming presence of large stones in the pipe

-          Continued recovery of high quality gems of up to 12 ct

-          Trial mining has yielded a total of 8043 ct to date at an average grade of 12.7 ct/100 tonnes

-          Revenue from Baoulé diamond sales to date of $700,644 from 5173 ct

-          Objective to mine and process 100,000 tonnes of kimberlite now 63% complete

-          Target resource of 3 Mct at Baoulé based on previous drilling and diamond results to date; to be confirmed on completion of trial mining 

Stellar CEO Karl Smithson says: “We are extremely encouraged to have recovered this 55 ct stone as it confirms that the Baoulé pipe is a possible source of the large diamonds which have been mined in alluvial deposits downstream of the Baoulé pipe for many years, several of which have been +100 ct in size.

We will carefully examine the stone which appears to have a ‘boart’ exterior and a potentially better quality diamond on the interior. Gem quality diamonds continue to be recovered from the Baoulé kimberlite up to 12 ct in size.  

“With approximately 63% of our trial mining and processing at Baoulé now complete, subject to the company having sufficient working capital, we are currently on track to finalise the trial mining and processing of 100,000 tonnes in the third quarter and look forward to providing further updates in due course.” 

Trial mining of the Baoulé kimberlite pipe resumed in late November 2015 after the rainy season, with stripping and mining of the western lobe. Extraction of the kimberlite started in December 2015 and processing of the material continues on a double shift basis (16 hours per day). The kimberlite material remains predominantly weathered, with increasing amounts of friable harder primary kimberlite at depth.  

The overall objective of the trial mining exercise is to extract and process up to 100,000 tonnes of kimberlite in order to determine with confidence the diamond grade and ultimate value of the pipe. The company remains on track to achieve this objective, having processed over 63,000 tonnes (dry) of kimberlite thus far. 

A total of 8043 ct have been recovered to date from Baoulé at a +1.25mm cut off, giving an average grade of 12.7 ct/100 tonne.

This grade is slightly lower than previously reported average grade of 13.5 ct/100 tonne due to an average lower grade for the west lobe (11 ct/100 tonne) as compared to the east lobe (13 ct/100 tonne). This seems to be a consequence of fewer smaller stones in the -7 sieve fraction and thus should not impact negatively on the gross diamond value.  

Recently a 55.64 ct diamond was recovered, which is the largest stone discovered to date at Baoulé. This is an unusual stone since it has a low quality (boart) coating but what seems to be a better quality diamond within the interior. The quality and potential value of the stone is currently highly uncertain and the stone will be carefully analysed to accurately determine its value before deciding on the sales process.  

A total of 610 stones greater than 1 ct have been yielded including numerous gem diamonds of up to 12 ct in size. The presence of the 55 ct stone confirms the company’s belief that the Baoulé pipe is a source of large diamonds and supports the investment thesis of a potentially lower grade but high value kimberlite orebody.  

www.stellar-diamonds.com

News courtesy of International Mining