Dickenson’s gold mine at Red Lake a steady producer over the years

Right next to Placer Dome’s Campbell mine is Dickenson Mines (TSE) Arthur White mine. They are close neighbors and work essentially the same type of ore in a similar geological environment. They have the same resourceful workforce that seems to characterize Ontario’s gold mining community and separate it from all others. Yet, what a difference in performance Campbell’s good fortune is hard to believe. High grade ore, good widths, continuity of both, a shaft that could scarcely be better located and the initial backing of a well heeled corporation long experienced in mining.

For Dickenson, one could almost say “none of the above.” In addition, the White mine was initially financed through equity, ensuring a rocky and uncertain ride to the operators who were trying to get a mine going. Yet despite those problems, the White mine has been a steady performer over the years.

Dickenson delivered the first ore to its original 100-tons-per-day mill in December, 1948. Capacity increased rapidly to 450 tons per day and in the last seven years has ranged between 750 and 800 tons per day.

Production to Dec. 31, 1990, totals 2,785,861 oz. recovered from 6,887,268 tons milled giving an average grade 0.40 oz. gold per ton.

Dickenson’s main shaft was located to develop the quartz veins first explored by surface trenching and diamond drilling. They were found to be erratic at depth and were abandoned as a significant source of ore below the fifth level (665 ft. below surface).

Thereafter, all mine development has been to the south of the shaft, initially to tap the extension of Placer Dome’s (TSE) Campbell mine most southerly zone and consequently called the “South C” by Dickenson. This has entailed a major expense to the company with cross-cutting a distance of 2000-3000 ft. on each level down to the 23rd. This was compensated to some extent by providing access to a number of mineable vein zones in the intervening ground.

From the 23rd level (3365 ft. below surface) an internal shaft has been sunk to a depth of 5689 ft. giving access to fourteen levels at 150-ft. intervals, the 24th to 37th. The lowest working level is the 30th and the lowest stoping is on the 28th. There is consequently a very large area to be explored and developed before further shaft sinking is needed.

Present ore reserves, proved and probable, are estimated at 3,155,000 tons grading 0.32 oz. plus 770,000 tons grading 0.30 oz. classed as “possible mineral inventory.” In total, there is sufficient ore to maintain the current level of production for 13 years.

Some 50% of the reserves are above the 23rd level thereby avoiding the charge of two stage hoisting.

The most important recent discovery is the “PLM” zone, named after the late Peter Munro, President of Dickenson from 1982 to 1987. Located parallel to and 500 ft. south of the “East South C” zone, the structure has a strike length of 2000 ft. and is still open. Widths vary from zero to 400 ft. Individual ore shoots range from 40ft. to 600 ft. in length and 6-100 ft. in width with grades of between 0.3 and 0.4 oz.

So far, the zone is known over a vertical range of 1000 ft., between the 24th and 31st levels. Current stoping and drift development is approximately 2900 ft. east of the internal shaft. This is an overall horizontal distance of 6,300 ft. to the main shaft, just short of one and one-quarter miles.

Both Campbell and Dickenson host a number of blind orebodies, the “PLM,” found in 1985, being the most recent discovery; the question therefore arises, how many others are there yet to be found? With Dickenson’s much more extensive network of workings, Dickenson has probably the better opportunity for finding out.