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

Pretium Resources Inc. June 18 reported that two long holes drilled from the underground workings at it Brucejack Mine confirm the presence of Brucejack-style mineralization starting from the eastern edge of the Valley of the Kings, the high-grade gold deposit currently being mined, to beneath Flow Dome, a gold zone about 1,000 meters east.

Surface drilling encountered bonanza grade gold at Flow Dome in 2015. Highlights from that program include 2.05 meters of 2,100 grams (67.52 ounces) per metric ton gold in hole SU-688.

Pretium said the mineralization drilled from surface at Flow Dome confirms the presence of either a new mineralized zone or an extension of the Valley of the Kings deposit.

Holes VU-820 and VU-911, each more than 1,500 meters long, tested mineralization continuity between Valley of the Kings and Flow Dome, while assessing the potential for a porphyry source at depth.

Hole VU-820, drilled 1,584 meters east at a minus-50-degree angle from the 1200 level at Valley of the Kings, encountered Brucejack-style gold in several areas.

Highlighted intercepts in VU-820 included 90.21 meters of 1.71 g/t gold, starting 442 meters east of Valley of the Kings. At 1,128 meters, the drill cut 1 meter of 46 g/t gold.

Hole VU-911, drilled 1,555 meters east at a steeper minus-65-degree angle, cut visible gold in several locations along its length.

The first visible gold was observed in a 0.9-meter intersection at 105.4 meters that averaged 157 g/t (5 oz/t) gold. Other highlights from VU-911 include: 1.5 meters of 142 g/t gold at 151.5 meters; 0.5 meters of 76.3 g/t gold at 161.5 meters; and 0.5 meters of 33.6 g/t gold at 802.29 meters.

Silver was also encountered in all the intercepts in both holes, include 1,825 g/t (58.68 oz/t) silver from 802.9 meters in VU-911.

Anomalous copper and molybdenum mineralization was also intersected at depth in both holes. The zone of anomalous mineralization extends at depths of between 1,400 meters and 1,485 meters in VU-911 and occurs more diffusely over a broader area in VU-820 – 1,260 meters to 1,585 meters down-hole depth. The mineralized zone in drill hole VU-911 corresponds with a downhole total field magnetic high, change in alteration, and the presence of a coarse porphyritic host rock. Pretium said pyrite grains from both holes show a transition from being zoned, like Valley of the Kings style, to un-zoned with inclusions of chalcopyrite, more in line with the porphyry mineralization at Seabridge Gold's nearby KSM project, further downhole.

Pretium said these features suggest increased proximity to porphyry style mineralization at depth below the Flow Dome zone.

A follow-up surface geophysical program will be initiated utilizing the data from the downhole in-situ electrode. The drill results along with the geophysics will be compiled to refine targeting of this zone for subsequent drilling.

Additionally, a geophysical survey is currently underway to refine high-priority targets for a 1,500-meter regional exploration drill program slated to begin in July.

This regional grassroots exploration program follows up on the comprehensive regional exploration that has previously been completed on the 1,250-square-kilometer (482 square miles) Brucejack property, including sampling, regional mapping, prospecting, airborne geophysics, ground geophysics, and hyperspectral mapping.

Pretium said this work has identified several distinct areas that have the potential to host mineralized zones similar to the epithermal gold-silver mineralization being mined from the Valley of the Kings and precious metals enriched volcanogenic massive sulfide mineralization found at Eskay Creek, a past producing high-grade gold mine about 25 kilometers (15 miles) to the northwest.

–SHANE LASLEY