Carleton
Gold was first discovered in Carleton, Yarmouth County, in 1886 but geological challenges made it difficult for historical prospectors to understand and work the site.
After the discovery of gold in the spring of 1886, the Carleton quartz vein was exposed that summer. A small crushing mill, driven by waterpower, was built by the end of the year at the bridge over the west branch of the Tusket River, half a mile from the mine. A shaft was sunk about 100 feet and 300 feet of levels (tunnels) were driven. About 50 tons of ore were taken out and several tests showed a yield of 2.5 ounces of gold per ton of ore, a very good rate.
In 1887, the property was sold by Messrs. Gale and Ross to Messrs. Hatfield and Uhlman. The shaft on the Carleton vein was sunk 100 feet deeper and a tunnel followed good ore to the east. The mill was replaced by a larger eight-stamp mill, which was still standing in 1919 when Geological Survey of Canada staff visited the mine. Forty-five ounces of gold were produced that year.
Some veins were prospected by a Mr. Turner on the adjoining property, and about 700 feet to the north Messrs. Miller and Crosby opened a belt (series of veins).
There was intermittent work done after 1887, but there are few detailed records of the activity. However, we know that in 1911, a two-stamp mill, operated by steam-power, was built at the mine, but in 1915 it was removed to the nearby Kemptville gold district.
Nearly all the gold produced in the Carleton district was from the Carleton vein. It was worked along a length of 315 feet by five shafts, to depths of 190, 100, 80, 80, and 80 feet, respectively. The vein averaged from 4 to 8 inches in width. In addition to gold, it contained much calcite, some arsenopyrite and iron pyrites, and a little galena and copper pyrite, minerals that could potentially be additional revenue streams for a modern gold mine if separating them proved to be economical.
The only other vein that produced was the Little vein, which was worked by open-cut for a length of about 200 feet and a depth of 30 feet. However, it did not produce much gold-bearing ore. (The vein was named because it was only three inches wide, not because of how little it produced.)
A total of 134 ounces of gold was produced in 1889, 1897, 1898 and 1899 from 130 tons of ore. Production was also reported for 1901, 1903, 1904, 1910 and 1911, totalling 145 ounces of gold from 393 tons of ore for those years.
Trifling amounts of gold were produced in 1914 and 1915 and mining in Carleton ended in 1915.
One challenge historically was a general lack of natural rock exposures (outcrops) in the area, which are often important clues for prospectors, helping indicate what minerals are present and where they are located. Without them, most knowledge of the area’s geology came from excavation, which was expensive and mostly done by hand. This hindered prospecting.
Another challenge was that the district contains several faults. In geology, a fault is a fracture, or zone of fractures, between two blocks of rock. Faults are caused by geological forces like tectonic plate movement, and they allow the blocks of rock to move relative to each other. Faults are a challenge in mining because they can cause deposits to be split, moving part of the deposit to a different, often hard-to-find, location.
The Little vein was split by faults and, because its extensions were never found beyond the faults, only one section of it was ever worked.
The Carleton vein was found in both directions beyond two faults. In 1909, E. F. Beeler sank a 70-foot shaft on its extension to the west but no gold was found. A thick quicksand prevented the vein being traced further west of this shaft.
To the east, the Carleton vein was found in several broken up, disconnected sections (see map below). Further along, the vein was whole, but no gold was found in it east of the faults.
While much of Nova Scotia’s gold is found in quartz veins, not all quartz veins contain gold. A number of veins found in Carleton were not auriferous (gold-bearing).
A bunch of other veins were also found. For example, the Iron vein had a 20-foot test pit dug on it, but no gold was extracted. Several other veins were also found near the Carleton mine but they also did not produce.
A few veins are said to have been cut by J. Morrison in a tunnel 1,200 feet west of the Carleton mine at the foot of the hill on the western side of Ryerson brook. A vein was also reported one mile north of the mine on the eastern side of Back Lake.
A large vein carrying gold and silver was found 1.5 miles northeast of the Carleton mine, on D. Carl F. Hilton's farm, near the north end of Fanning Lake. A 30-foot shaft and an open-cut 30 feet east of the shaft were dug.
Gold float (pieces of gold-bearing ore eroded from bedrock deposits) was found in several places. Float is an important clue for prospectors that can help locate the source veins. It was found, for example, 275 feet west of the Carleton mine on the eastern side of Burkee's Meadow, and to the north in the vicinity of the Iron lead. However, the parent veins were never discovered (https://notyourgrandfathersmining.ca/panning-for-gold).
Carleton has been prospected on and off since mining stopped in 1915. While it has gold that could potentially lead to a modern mine being opened, exploration in recent years suggests the area may have limited potential for disseminated gold – tiny flecks of gold scattered throughout host rock in addition to gold in quartz veins.
Modern science makes it possible to extract gold from both veins and the surrounding rock. This is a major advantage for a gold mine for two reasons. First, it increases the overall amount of gold available to be extracted. Second, it often means a deposit can be mined with a surface mine since gold disseminated throughout the rock can be extracted and milled relatively inexpensively from surface, compared to the challenge of chasing narrow veins in an underground mine. Underground mines are generally more expensive to operate than surface mines.
A number of Nova Scotia gold deposits contain disseminated gold, which strengthens the business case for opening modern mines on them. For example, the modern Moose River gold mine, which closed earlier this year because the deposit has been mined out, contained significant quantities of disseminated gold in addition to auriferous quartz veins.
Unfortunately, disseminated gold is not an advantage that Carleton appears to have, based on our current knowledge of the area. However, as more exploration is done, and science and technology advances, there is no telling what else we might learn about the site and what its potential could be. Disseminated gold is an example of this – historical gold miners mostly extracted only gold that was visible to the naked eye, but modern science makes disseminated gold valuable today in ways that our early miners could never have imagined.
