Avino trying to revive mining at B.C.’s Bridge River camp

The Bridge River area, about 100 miles north of Vancouver, was once one of the most prolific mining areas in Western Canada. Placer gold was originally discovered in the area in 1863 with the two major mines, the Pioneer and Bralorne, coming into production in 1928 and 1932 respectively.

Adjacent to one another, the Bralorne and Pioneer were merged in 1959 and operated continuously until their closure in 1971. The mines produced over 2.5 million oz. gold from 1932 to 1971, milling a total of 5.4 million tons grading an average of about 0.53 oz. gold per ton.

Avino Mines & Resources (VSE) hopes to revive the camp, having acquired a 100% interest in the old mine properties, as well as already holding a 100% interest in some very prospective ground to the north of the former producers. Avino purchased the Bralorne and Pioneer mine property in November, 1991, from E & B Explorations, International Corona, Cathedral Gold and Geomex Development for a total of three million common shares. The shares are restricted from resale until Nov. 29, 1993, and Avino has the option of buying back up to 1.5 million at $1.20 per share until that date. E & B Explorations and its partners conducted extensive exploration on the Bralorne/Pioneer property from 1980 to 1985, including both surface and underground drilling in an attempt to outline additional reserves. Expenditures during the period totalled $8.29 million.

The reserve inventory at the time was estimated at about 920,000 tons grading 0.26 oz. gold per ton at a cutoff of 0.14 oz.

In 1988, Corona undertook a program of surface and underground drilling and underground mapping and sampling, as well as drifting and rehabilitation at a total cost of over $3 million during the year.

Corona described its results from the program as generally disappointing, finding that much of the previously estimated reserve inventory is inaccessible because of interference from old workings. Accordingly, Corona estimated the accessible mineral inventory above the 800 level at about 56,500 tons grading 0.33 oz. gold at a cutoff of 0.20 oz.

Total reserves above the 2,600 level were estimated by Corona at about 208,000 tons grading 0.3 oz. gold.

Based on previous underground and surface drilling data, Avino’s estimate of proven and probable reserves above the 800 level total 182,000 tons grading 0.43 oz. gold at a cutoff grade of 0.14 oz.

Proven and probable reserves between the 800 and 1000 levels are estimated at 49,000 tons grading 0.24 oz. gold, while proven and probable reserves between the 1000 and 2600 levels stand at 688,000 tons grading 0.24 oz. gold. The old mine workings are accessible from the Cadwallader Creek valley by adit into the 800 level. From the 800 level to the deepest point in the old operation represents almost 4,000 ft., while the distance to surface outcrop above measures more than 1,000 ft.

Reached by a number of internal shafts, all the workings below the 800 level are now flooded.

Avino’s primary interest at the present time is its discoveries to the north of the King area of the Bralorne mine. All of Corona’s work concentrated on the old Bralorne and Pioneer mines, generally ignoring the King area. Old workings in the mines are bounded on the northeast by the Fergusson Thrust and the Cadwallader to the southwest with the old King, Bralorne and Pioneer mines strung out between the structures from the northwest to the southeast respectively.

The area to the northeast of the Fergusson was always considered barren by previous operators with a thick blanket of overburden making exploration difficult.

Avino’s discovery of two veins to the north of the Fergusson excites Jim Miller-Tait, Avino’s project geologist. He now believes the veins represent the fault offset along the Fergusson Trust of the King and North veins from the King area of the Bralorne mine.

If the two discoveries do represent fault-offsets, there is considerable exploration potential along the north side of the Fergusson thrust for offsets to a number of rich mined-out veins in the Bralorne mine. The two parallel veins, called the Peter and Millchuck, are spaced about 900 ft. apart on Avino’s Loco property to the north of the recently acquired Bralorne property.

In 1989 Avino completed a short adit to the Peter vein and drifted on it for about 215 ft. Sampling along its 215-ft. length returned an average gold grade of 0.38 oz. gold over 3.4 ft. The last 105 ft. of that averaged over 0.6 oz. gold.

Gold mineralization is similar to Bralorne/Pioneer, associated with arsenopyrite and pyrite in banded quartz veins. Previous operators achieved up to 97% recoveries using gravity-flotation or gravity-cyanidation with 65% of the gold free-milling.

Miller-Tait said the Peter vein has been traced on surface for about 2,000 ft. Surface drilling on the downdip projection of the vein has returned mixed results, varying from 0.039 oz. gold over 5 ft. up to 0.33 oz. over 7 ft. In 1991 Avino rehabilitated a portion of the underground workings in the King area on the 800 level, to allow access for underground drilling on the downdip projection of the Peter vein. The drilling encountered better results, with two holes returning high-grade intercepts of 1.1 oz. gold over 6 ft. and 0.51 oz. gold over 9.4 ft. Pierce points for the intercepts were one above another, separated about 60 ft. vertically at the 800 level. Louis Wolfin, president of Avino, said the company’s first priority will be to fully rehabilitate the access on the 800 level to the Peter vein, drift on it to the high-grade intersections and then complete a raise to the adit and drift about 1,000 ft. above.

Blocking out additional ore reserves would move Avino a step closer to bringing the property back into production.

Taking into account the infrastructure now in place — offices, camp, mill building and underground workings — preliminary studies indicate the property could be brought back into production for as little as $5 million including working capital.

The study is based on a 300- to 400-ton-per-day mill fed from unmined ore in the old workings.