Lower Sackville

In September 1921, Frederick W. Dixon was prospecting a quartz vein in a rock outcrop in Lower Sackville, just west of the corner of Cobequid Road and Legacy Court today. He took samples of the quartz to the Provincial Museum (now called the Nova Scotia Museum) on September 23 for analysis.

He continued prospecting and found that the vein widened from 2¾ inches in the outcrop to six inches or more. On October 3, he found another mineral within the quartz vein and, not knowing what it was, he brought more samples to the Museum.

It turned out to be scheelite, a mineral from which the metal tungsten is often extracted. Nova Scotia has a number of known tungsten deposits, several of them hosted in scheelite.

Harry Piers, who had considerable expertise in geology and mineralogy and was the curator of the Provincial Museum, advised Dixon to stake a claim wherever he had found the samples – Dixon had not revealed the location to Piers to keep his discovery secret.

Dixon staked his claim and revealed the location to Piers on October 10.

Dixon continued working the site, employing a few men, and produced “a considerable amount of fine-looking ore, very promising large samples of which were brought to the Museum on October 22 and in January,” according to Piers.

Winter forced Dixon to suspend work but he continued in spring 1922, extracting more ore “of excellent quality,” Piers wrote.

Piers visited the site on May 3, 1922. At that time, there was a small trench “of irregular shape,” about 32 feet long, 15 feet wide at its widest point, and about nine feet deep at the northeast end.

Most of the ore-bearing quartz had been blasted out and taken to a nearby barn, but some still lay on bottom of the trench.

Dixon told Piers that the quartz vein had been as wide as 18 inches at one point.

Piers’ advice to Dixon was to keep following the vein “wherever it may lead,” in the hope that it would allow him to discover a main vein that would “be more regular and extensive, and it is to be hoped as well mineralized.” The amount of ore in the vein Dixon was then working “should at least pay for this exploratory work.”

Piers wrote that “A number of barrels of good ore were shown, all of which had been taken out of the small pit described. Judged as a prospect only, which so far it only is, it seems to me to be one of the very best Scheelite discoveries that has yet been made in this province, and the deposit decidedly deserves to be further investigated.”

Perhaps to thank Piers for all his help, Dixon donated a sample of the Lower Sackville quartz to the Provincial Museum’s mineral collection.

Frederick Dixon’s prospecting at the site came to an end but, per Piers’ advice, more exploration took place over the years. In 1937, F. R. Hyland dug a trench 15 metres long and 3-5 metres deep on a 20-centimetre-wide quartz vein. He extracted several tons of scheelite but reportedly none were shipped.

A 1939 government memo recommended the then-water-filled pit be drained so additional exploration could take place. Most of the vein was underwater at that time. The drawing below was appended to the memo.

In 1940-41, several operators did very small amounts of prospecting and in 1942, J. W. Storer of Frontenac Silica Sandstone Ltd. sank a shallow shaft 50 metres northeast of the trench. A 23-centimetre-wide vein was opened and a 400-pound bulk sample was extracted.

The exploration in the early 1940s took place because tungsten was a critical mineral during WWII. It was used as filaments in lightbulbs and, because it is the metal with the highest melting point (3,422 °C), in plane engines and munitions. The black and white picture below was taken in 1942.

Tungsten is still used in light bulb filaments. It is also often mixed with other metals to make alloys that have high temperature tolerance, high corrosion resistance and excellent welding properties. These superalloys are used in the aerospace and automotive industries in things like airplane turbine blades and wear-resistant parts and coatings.

In 1959, six diamond-drillholes were put down by Froberto Mines Limited over a strike length of 130 metres. Each hole apparently intersected scheelite-bearing veins.

Lower Sackville has grown considerably since then and all evidence of the historical workings has been eliminated by development in the area. Apartment buildings, pictured below, now stand on the site.

There have been a number of discoveries of tungsten in Nova Scotia, usually in close proximity to gold deposits. For example, the Lower Sackville tungsten deposit is not far from, and linked geologically, to the nearby Waverly gold district. Tungsten was also found in Waverley, northeast of Perry Lake, in 1908.

It remains a bit of a geological mystery why some Nova Scotia gold districts have significant amounts of tungsten associated with them and other gold districts do not. Given the global interest in Nova Scotia’s gold deposits, maybe future exploration will help us better-understand our potential for tungsten.

While it is sometimes called a mine, the Lower Sackville tungsten workings, like many other historical operations, were not a mine in the sense that we use the word now. Historical mines were often pits just a couple feet deep, or a small shaft or two, often even without a mill for processing. These historical “mines” often saw very little actual mining or production. Today we call such sites prospects.