by Greg Klein | March 9, 2015
Canadian diamonds distinguish themselves more by value than size, but an 11-carat Northwest Territories rough stone now fills a gap in the Royal Alberta Museum mineral collection. The recent purchase from Dominion Diamond’s (TSX:DDC) majority-held Ekati mine “fills a specific need in our collection and for a display that we’re hoping to put together in the future,” says Melissa Bowerman, assistant curator of geology for the Edmonton facility.
Impressive as it is for size, “it’s fairly included so it probably wouldn’t have been appropriate for cutting anyway,” Bowerman points out. “But it’s a stunning, intact specimen.”
She describes it as “fairly colourless. It does have a tint of yellow but the inclusions give it a bit of a grey tone. It does have etched, triangular pits in it. The diamond shows signs of being unhappy as it rose in the magma and became etched. So you get these beautiful little triangular pits.”
She declined to divulge the price for security reasons.
“We don’t see a lot of very large diamonds coming out of Canadian mines and that has a lot to do with how the ore is processed,” she adds. “I think the maximum size is maybe on the order of 20 carats. That doesn’t necessarily mean large Canadian diamonds don’t exist. They may not survive the processing. I think it’s a more efficient type of processing that doesn’t recover very large stones.”
The 11-carat addition’s now on temporary display with the museum’s mineral exhibit “which includes a gem collection featuring most of the major gemstone families and some of the more unusual types of gemstones. We try to have both rough and cut examples. One thing we didn’t have was a large, display-quality rough diamond, which seemed like an oversight considering that Canada produces them.”
“Of course people love the gems,” Bowerman says. Among the museum’s highlights is a “big amethyst geode that people remember. We have an outstanding imperial topaz, actually two rough topazes and we also have quite large-carat emeralds, rubies, the usual families. Then there’s some weird things like sphalerite and other things you wouldn’t expect to be cut into gemstones. There’s a range of precious and semi-precious gemstones.”
The museum gets its rocks through purchase, donation or field collection from global sources “to show the full spectrum of the mineral world and geology in general.” Among the Canadian stuff is “an outstanding collection of gold from the Bralorne mine. It’s probably one of the best historical mining collections we have.”
Bowerman plans to make the Ekati stone a permanent feature of an expanded mineral exhibit when the new downtown Edmonton location opens as western Canada’s largest museum in December 2017.