North of 60 Mining News - The mining newspaper for Alaska and Canada's North

North Arrow Minerals Inc. April 5 announced the discovery of a new kimberlite during a 607-meter drill program carried out this winter at the company's Loki diamond project in the Lac de Gras region of Northwest Territories.

Roughly 19 miles (30 kilometers) southwest of the Ekati Mine and 15 miles (24 kilometers) west of the Diavik Mine, Loki is found in a region known for its rich diamond deposits.

North Arrow narrowed down the drill targets at Loki with surface sampling completed in 2016 and geophysical surveys carried out last year.

This work turned up several prospects, including target 465, a very prominent circular geophysical anomaly at what appears to be the up-ice end of a diamond-bearing kimberlite indicator minerals train.

Target 465 was initially tested with a south oriented drill hole that encountered granite country rock with intermittent, non-magnetic mafic dykes and localized fracturing down to a depth of 142 meters. A second hole drilled about 30 meters to the west encountered a 20.85-meter interval of black to olive green kimberlite.

North Arrow said this kimberlite is generally altered and kimberlite indicator minerals including altered olivine and rare garnet have been observed. The company said orientation of the two holes suggests Kimberlite 465 may dip steeply to the south.

In addition to the discovery of 465, a single drill hole tested the central portion of the EG05 kimberlite.

EG05 was tested with three holes in 1999, all of which cut kimberlite over their entire length. This year's hole was drilled to gain a better understanding of diamond distribution within the kimberlite.

This vertical hole encountered resedimented volcaniclastic kimberlite below 17.5 meters of ice, water and overburden and ended in volcaniclastic kimberlite at a depth of 169 meters.

Detailed logging of the kimberlite intervals from 465 and EG05 will occur over the next week, which will include sampling for kimberlite indicator minerals and microdiamonds. Additional drilling is required to evaluate the size, orientation and internal geology of the 465 and EG05 kimberlites. Loki also hosts a number of untested drill targets with good kimberlite indicator mineral support.

Crews prepare the drill to be moved after drilling a vertical hole down the EG-05 kimberlite at Loki.

Planning is underway for a summer drilling campaign to continue evaluating this prospective area of the Lac de Gras region.

"The Lac de Gras kimberlite field hosts the Ekati and Diavik diamond mines, which have produced in excess of C$20 billion in rough diamonds over the last 20 years, and today's announcement highlights that the region, and particularly North Arrow's Loki and LDG Diamond Projects, remains prospective for new discoveries," said North Arrow President and CEO Ken Armstrong.

"North Arrow is planning drilling campaigns at both Mel and Loki during the summer of 2018 as well as at our LDG (Lac de Gras) joint venture property with partner Dominion Diamond Mines," he added.

Funding for the winter program, which resulted in the discovery of Kimberlite 465, benefited from the Northwest Territories Mining Incentive Program.

–SHANE LASLEY