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36 E&MJ; • OCTOBER 2017 www.e-mj.com NORDIC MINING 2017 thorities subsequently reallocated the mining license for the deposit to the company's former mining contractor, LNS Greenland. LNS then formed Greenland Ruby as the new license-holder for Aappalut- toq, also being responsible for market- ing the mine's output of rubies and pink sapphire — both types of corundum. The hard-rock deposit is hosted in an Archean anorthosite complex consisting of multiple layers of mafic to ultramaf- ic rocks. According to True North Gems, corundum found in micaceous primary ore is relatively easy to extract, whereas secondary gabbroic ore is harder, making the recovery of unbroken stones more difficult. Around 5% of the corundum is high-end gem grade, a further 20% is "near-gem," and the remainder is "com- mercial" quality. Speaking at the official opening of the mine, LNS CEO Gunnar Moe said, "We are extremely proud to be the first com- mercial gemstone mining operation in Greenland, and look forward to entering the marketplace with ruby material that can match that from traditional sources such as Burma, Thailand or recent find- ings in Mozambique." Recovery of the gem material involves initial crushing, followed by scrubbing, some hand sorting, re-crushing oversize, dense-medium separation and optical sorting. Final cleaning with hydrofluoric acid results in a concentrate that is sent to the company's sorting house in Nuuk for grading and subsequent marketing. ... and Maybe From Finland? In August, one of the junior companies exploring for diamonds in Finland, Kare- lian Diamond Resources, published the results of a preliminary economic assess- ment on its Lahtojoki kimberlite pipe in southeastern Finland. The study suggests that capex of $22 million would be need- ed to develop an open-pit operation there, with the potential for producing more than 2 million carats (ct) of diamonds over a nine-year life. As the company pointed out, this would be the first Euro- pean diamond mine outside Russia. Drilling has indicated an inferred re- source of 5.6 million mt to a depth of 160 m, containing a non-JORC estimate of 2.225 million ct. Chairman of Karelian Richard Conroy said, "Clearly much work remains to be done, but this report is a major and very encouraging step forward in our assessment of the Lahtojoki dia- mond project and of its potential for de- velopment as a mine." In addition to Lahtojoki, the compa- ny is also evaluating the Riihivaara and Seitaperä kimberlites in the same dis- trict, with the aim of confirming that di- amondiferous deposits occur in the Finn- ish section of the Karelian Craton as well as on the Russian side of the border. It has a confidentiality agreement with Rio Tinto over data from previous exploration in Finland, with Rio Tinto having the op- tion to earn a 51% interest in any project that Karelian identifies. Karelian is only one of several com- panies that have looked at Finland's di- amond potential in recent years. One of the earliest, the local copper-mining company Malmikaivos Oy, began work in the 1980s together with Australia's Ash- ton Mining, while European Diamonds (a forerunner of today's Firestone Diamonds with operations in Lesotho and Botswana) The production of industrial minerals is of major importance in Norway. In operation for the past 20 years, the Brønnøy Kalk quarry, near the country's coast about 120 km southwest of Mo I Rana, supplies high-quality calcium carbonate for use in the paper industry. (Photo: Roar Berg-Hansen)