Firestone Diamonds (LON:FDI) has recovered a batch of very rare type 2 diamonds from its Liqhobong mine in Lesotho and found an even rarer blue diamond.
Both finds were highly significant, Firestone said, especially the batch of 28 type 2a diamonds as these occur predominantly as high quality, high colour crystals and are extremely rare.
The world's diamond production comprises approximately 98% of type 1A diamonds while less than 2% are the high quality, white and colourless type 2 stones.
The identification of a small blue diamond, meanwhile, confirmed that the Liqhobong mine's diamond assortment is diverse.
The mine is also still relatively untested in terms of its ability to produce diamonds of high quality and size, the company added.
The diamonds, which were recovered in August and September, are a very exciting find said independent valuation consultant Johan Erikson, especially the type 2 diamonds and the increase in colour, shape and quality.
“The increased recovery of unbroken, higher quality good colour crystals in the middle and coarser size fractions currently on tender should bolster the prices of the company's stones," he added.
Firestone added that a 27 carat, fragmented stone was also recovered in September and when reconstructed appears to have originated from a stone in excess of 200 carats. At present, the pilot plant at the mine is not able to recover diamonds with dimensions bigger than 25mm, such as the stone in question.
Tim Wilkes, Firestone’s chief executive, added: "The recovery of the rare type 2 diamonds and the increase in quality and the variety of colour endorses the directors belief that the Liqhobong resource contains significant upside, which will be fully realised once production is increased via a much larger, fit for purpose treatment plant."
"The increase in quality and the potential for very large stones to be recovered through an expanded treatment plant is extremely exciting and demonstrates the value the company is gaining from the current pilot plant operation."
Firestone added its expects to release a definitive feasibility study for the expansion of production from 200,000 carats per annum from the pilot plant currently, to over 1 mln carats by 2015 with a new treatment plant to handle the large diamonds being found at Liqhobong.
Firestone began operating its pilot plant in June 2011, since when it said it has recovered significant quantities of vivid and yellow fancy diamonds, two small, light pink diamonds and a number of high quality white stones and can now confirm the presence of rare type 2 diamonds.