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

White Rock Minerals Ltd. Sept. 19 said it has identified another prospect to add to a growing list of drill targets at Red Mountain, a high-grade zinc and precious metals volcanogenic massive sulfide (VMS) project in Alaska.

Red Mountain already hosts two zinc-lead-copper-silver-gold deposits – Dry Creek and West Tundra Flats (WTF). At a 3 percent zinc cutoff grade, these deposits host 9.1 million metric tons of Australian Joint Ore Reserves Committee- (JORC) compliant inferred resource averaging 5.8 percent (1.17 billion pounds) zinc; 2.6 percent (516 million lb) lead; 0.1 percent (26.5 million lb) copper; 157 grams per metric ton (46.1 million ounces) silver; and 0.9 g/t (260,000 oz) gold.

White Rock and its joint venture partner Sandfire Resources NL are focusing the 2019 exploration program on investigating the district-scale potential across the 183-square-mile (475 square kilometers) Red Mountain land package.

"The potential for multiple VMS deposits throughout the company's large strategic tenement package, expanded to 475 square kilometers last year, is only now beginning to be understood," said White Rock Minerals Managing Director Matt Gill.

During the latter half of the season, crews carried out reconnaissance at Cirque, a historical prospect covered by a small block of claims White Rock staked south of the main Red Mountain land package.

Discovered by Resource Associates of Alaska, Getty and Phelps Dodge in 1976, the Cirque prospect hosts blocks of massive sulfide float that measure up to two meters thick that are within 300 meters of mineralized outcrop. Assays from 18 samples collected in this area averaged 5.6 percent zinc, 1.7 percent lead, 49 g/t silver and 0.5 percent copper.

A surface geophysics crew recently completed a single fixed loop electromagnetic survey across two horizons of massive sulfide that extend east under glacial till cover. Modelling of the results by Newexco – a specialist geological and geophysical consulting firm – shows anomalous response on all four lines, consistent with a single conductive horizon with considerable strike and depth.

White Rock Minerals Ltd.

White Rock said the conductance is low, which may be consistent with a VMS horizon containing weakly conductive lead-zinc sulfides. A second conductive horizon to the south is very weak with further surveying likely required to better define this feature.

"Our first ground geophysics survey on a historic prospect has identified the type of conductor that could reflect significant massive sulfide accumulations," said Gill. "We continue to be excited by the targets being generated and the opportunities that presents for follow-up drilling."

The Australia-based explorer said Cirque is the highest priority of several prospect identified for follow-up.

"A nice discovery to make, and this will be added to our list of drill targets we still have ahead of us," said Gill. "These targets yet to be drilled include Artesia, Irish Knob, Black Top, Grizzly, Kettle and Glacier Creek East."

–SHANE LASLEY