GEM PRODUCTION AND POTENTIAL IN CANADA

Canada has been a diamond producer since the Ekati mine opened in the NWT in 1998. The neighbouring Diavik mine opened in 2003 and the Snap Lake (NWT) and Victor (northern ON) mines in 2008. Production peaked at 19M carats in 2007 and was 10.80M carats in 2011. The Renard mine in northern QC will open in 2014 and the Gahcho Kué mine in the NWT is scheduled to open in 2015-17. With respect to other gems, Canada produces ~75% of the world’s jade, almost all nephrite from BC, and has the most reserves. Over 90% of the world’s production of Ammolite, a gem material composed of aragonite derived from the shells of ammonites, is from open pit mines southwest of Lethbridge, AB. Amethyst is produced from ~14 mines within a 40 × 195 km area near Thunder Bay, ON. Examples of small artisanal producers include the Princess Sodalite Mine near Bancroft, ON, and granitic pegmatites in the O’Grady batholith (NWT), which have produced small quantitities of gem tourmaline since 2006.

Recent discoveries have been encouraging in terms of the eventual production of other gem materials from Canada. Ruby and sapphire were discovered near Revelstoke, BC in 2002. The corundum formed on the borders of Cr- and V-bearing mica-feldspar layers in marble via the prograde reaction muscovite → corundum + K-feldspar + H₂O at the peak of metamorphism. Sapphire was discovered on Baffin Island in 2006. The corundum occurs in nepheline-bearing calc-silicate lenses which may have crystallized from a desilicated syenitic magma emplaced into marble late in regional deformation. Fracture-controlled alteration of nepheline within scapolite “capsules” localized corundum crystallization. Gem spinel, sometimes associated with sapphire or lapis lazuli, occurs at a number of localities on Baffin Island in NU.

Chromium-dominant emerald has been described from the Tsa Da Glisza deposit in the YT, the Taylor 2 occurrence in NW ON, and the Anuri prospect in NU. Vanadium-dominant emerald occurs at the Lened property in western NWT. Green beryl discovered near the Mountain River, NWT, in 2007 is proposed to have resulted from inorganic thermochemical sulfate reduction via the circulation of warm basinal brines through sedimentary rocks and represents a variant of the Colombian-type emerald deposit model.