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Presently around $22 billion worth of diamonds are sold at wholesale prices every year, but the introduction of a regulated exchange could push that to $100 billion, Philion said. He added that it has been 20 years since the last significant kimberlite pipe was discovered. Since then, overall diamond production has been in decline. For investors, it's those stones above 10 karats and that sport unusual colors forged by nature that are in demand, said Philion. "White or fancy colors such as pink, brown, red and green usually qualify as investment grade, Philion said. "There are not a lot being found but those that are, tend to appear in Lesotho." Diamonds are classified into two cate- gories: Type I diamonds that contain nitro- gen; and Type IIa diamonds, which are nitrogen-free. It is the latter that show col- ors, and is also the gem type with which Lesotho is particularly blessed. Some of the largest diamonds ever dis- covered have been found at just one oper- ation, the Letšeng mine run by Gem Diamonds not far from Paragon's projects. Like Paragon's planned operation, Letšeng comprises several kimberlite pipes and has steadily produced spectacular finds since excavation began in the late 1950s. The biggest stones range roughly between 500–600 karats uncut, or about the size of a chicken's egg. These have gone on to be "named" diamonds—jewels so spectacular that they are given their own moniker. For instance the 603-karat "Lesotho Promise," discovered at Letšeng in 2006, ranks as the world's 12th largest diamond. It was sold for $12.4 million, to London- based investment jewel specialist Graff Diamonds, and following a year of pain- staking work was cut into 26 "Flawless D" jewels to be fashioned into a single neck- lace. Graff estimates its value at around $50 million. Since Gem Diamonds began operating Letšeng in 2006, the mine has unearthed four of the 20 largest white gem-quality diamonds ever recorded. Last year's major discovery was a 198-karat gem that made headlines around the world. (See related story on p. 5) All in all, Lesotho has at least 39 dis- covered kimberlite pipes, of which 24 are diamondiferous. Most of these are already claimed and although there's plenty of exploration going on, there are no guaran- tees that more will be found. If Paragon and its Gulf backers' gamble pays off, high-value diamonds could take their place with gold as a store of long-term value. "For the foreseeable future, I see the appeal of diamonds as an investment lim- ited to high-net-worth individuals, those looking to store value, using diamonds as an additional portfolio diversification tool, with the added benefit being the very high value-to-weight ratio diamonds provide," said Zimnisky. Kinross Considering Two-phased Expansion for Tasiast Kinross Gold is completing early-stage engi- neering work on a potential two-phased expansion at its Tasiast gold mine in north- west Mauritania. A feasibility study of an initial phase one expansion to increase mill throughput capacity from the current 8,000 mt/d to 12,000 mt/d is scheduled for completion in the first quarter of 2016. Following deferral in early 2014 of a previously studied 38,000-mt/d mill expansion, Kinross has continued to explore alternatives to realizing Tasiast's growth potential in the current gold price environment. Based on work to date, the company believes a phased approach would have the benefit of leveraging exist- ing mill infrastructure to optimize the cur- rent operation in the near term. At the same time, capital costs for the Phase One expansion are estimated at $290 million, sharply lower than the $1.6 billion feasi- bility study estimate for the previously con- sidered 38,000-mt/d expansion. Work to date on Phase One contem- plates installation of an oversized semi- autogenous grinding mill and gyratory crusher to increase mill throughput capac- ity by 50%, as well as addition of three leach tanks and improvements to other components of the processing circuit. Once commissioned, the additional crush- ing and grinding capacity is expected to enhance processing of the harder, higher- grade ore in the Tasiast property's West Branch zone and, by extension, to improve Tasiast's production and operating costs. Tasiast produced 165,339 gold equiva- lent oz during the first three quarters of 2015 at production costs of $1,042/oz. Under the Phase One expansion scenario, production during the first two years of operation would increase to 368,000 oz/y at estimated all-in costs of $725/oz. Construction time for the Phase One expansion is estimated at two years. Phase Two expansion under current planning would continue to have the poten- tial to increase throughput capacity to as much as the previously considered 38,000 mt/d. Such an expansion would include installation of additional milling, leaching, thickening, and refining capacity. Tasiast is an open-pit operation located approximately 300 km north Mauritania's capital, Nouakchott. Gold mineralization occurs in two parallel trends: the currently mined Piment Zone, which is continuous over a 4.5-km strike length, and the West Branch zone, with a strike length of approximately 1.5 km. Proven and probable reserves as of year-end 2014 totaled 162 million mt at a grade of 1.77 g/mt containing 9.2 million oz of gold. The deposit is open along strike and at depth. Kinross acquired its 100% interest in the Tasiast mine in September 2010 when it completed its acquisition of Red Back Mining Inc. DECEMBER 2015 • E&MJ; 23 www.e-mj.com REGIONAL NEWS - AFRICA Kinross Gold is looking at ways to expand daily production from its Tasiast mine by 50%.