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Simpson Mine
1992
Simpson Mine Shaft, Bruce Mines, Ontario, Canada

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The Simpson Mine was one of many that were being worked in 1848. In August 1992 the restored Simpson Mine shaft was officially presented to the public with a recreated horse whim, open head frame, and shop displaying artifacts of the original mining days. The Simpson shaft was chosen for restoration over other shafts due to accessibility and cost efficiency. The mine was approximately 100 feet (30m) long and originally 45 feet (15m) deep. For safety reasons, the shaft was filled in to a depth of about 12 feet and a pumping system installed to keep it dry.

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Model of the reconstructed Simpson Mine Shaft.
1992
Simpson Mine Shaft, Bruce Mines, Ontario, Canada

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Quartz vein
2005
Simpson Mine Shaft, Bruce Mines, Ontario, Canada

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This is a vein of white quartz, surrounded by black diabase. When searching for copper the early prospectors would have cleared areas of trees and brush looking for this type of vein, which also may have had the green stain of malachite showing.

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Ore samples
2005
Simpson Mine Shaft, Bruce Mines, Ontario, Canada

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Mineral Samples

1. Native copper, very close to pure copper. This sample was found on the south shore of Lake Superior.
2. Malachite - The green coloring from the malachite would be absorbed into surrounding wood or bones. Where there was malachite, there was usually copper.
3. Bornite - The small grey fragment in this quartz contains 80% copper.
4. Chalcopyrite - In this area chalcopyrite contains around 35% copper. It has been referred to as fool's gold, which is not technically correct since iron pyrite is fool's gold.
5. Chalcocite - Contains 80% copper.
6. Native copper

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In the Simpson Mine the chalcocite and bornite were found in approximately the first 12 feet of the mine. Below this fairly narrow band, the chalcopyrite started, which contains only 35% copper. Since they did not refine the ore on site, mining ore with only 35% copper, with a loss of 5% in their processing, and then shipping it across the Atlantic for refining, was not profitable. The Simpson mine was worked for a year; going to a depth of 45 feet and then being closed in 1849 due to the low copper content in the ore.

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Skimpings
2005
Simpson Mine Shaft, Bruce Mines, Ontario, Canada

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The landscaping gravel surrounding the Simpson Mine shaft is actually the skimpings, the left over, or waste rock, from the Simpson Mine. These "skimpings" often contained 1-2% copper.