Smithfield, Colchester County

An historical lead mine in Smithfield is an example of how the geological forces that create mineral deposits can also be obstacles to mining them.

Lead was discovered in Smithfield, Colchester County, in 1880 by H. Clarke who dug two shafts and built a small lead smelter with which he milled 100 tons of ore. (This site should not be confused with Smithfield, Guysborough County, where there was also a historical lead mine. See its story at

A third and fourth shaft were dug and a further 300 tons were milled in 1884. Several hundred more tons were processed over the years following.

Around 1889, small amounts of silver and gold were discovered at the site, but work ceased.

A major challenge for the mine was a lack of funds and experience in building and operating a smelter. (Smelting is the process by which a metal is extracted from ore, its host rock, by heating the metal beyond its melting point.)

A metallurgist from Swansea, Wales, “happening to be in Halifax,” according to an 1887 prospectus for the mine, was hired to build the smelter. Swansea was an important centre of metalworking in the 1800s so having someone from Swansea was presumably seen as an asset for the project.

However, “an entirely insufficient sum” was raised to build the smelter and the smelting plant was “hurriedly erected, the promoters of the enterprise expecting to pay for the further development of the mine by the sale of the product from the smelter. They were doomed to disappointment, as the smelting works proved an entire failure.”

An examination by another metallurgist, from Boston, found that the ore was “easily smelted, but, as the promoters had exhausted their capital, the works were shut down….”

Interestingly, the 1887 prospectus calls the site the “Joe Howe Mines.” This was presumably a reference to former premier Joe Howe, who passed away in 1873, but it would have been very unusual to name a mine in honour of a politician who had passed away years before the deposit was discovered. Mines are usually named for their location or the companies that own them. The company’s prospectus is the only place we have seen the mine referred to by the Howe name.

After the smelter debacle in the 1880s, the mine was largely inactive until the mid 1920s when the workings were dewatered and the No. 2 shaft was deepened to 50 metres. Some tunnelling was also done.

From 1951-1953 Minda Scotia Mines Ltd. carried out an extensive exploration of the deposit that included diamond-drilling, geophysical surveys and the sinking of a cement collared, three-compartment shaft north of the existing shafts.

The company intended to sink the shaft to 100 metres but stopped at 65 metres because highly fractured and jointed rock was encountered. These conditions required heavy timbering to support the shaft’s sides, which increased costs.

Additional exploration at Smithfield has taken place from the 1970s through to today.

As a result of all this exploration, we know now that the site contains two mineralized zones. One is a lead-zinc deposit, and the other, immediately to the east, contains pyrite (fool’s gold) and minor levels of lead and zinc. The site also contains small amounts of barite, silver and gold.

While each deposit is unique, metals deposits often form as a result of tectonic plate collisions. The heat and pressure caused by two tectonic plates colliding and rubbing against each other for millions of years can cause earthquakes and melt rocks in Earth’s crust.

It can also cause faults and fractures in rock. Faults are cracks in Earth's crust along which blocks of rock move relative to each other, and fractures are cracks in the crust where there is no movement.

Faults and fractures often help create deposits because they allow magma and other fluids to leach a variety of minerals from rock deep underground and flow into cracks in rock closer to surface. The fluids cool and harden, forming the deposits.

Many of Nova Scotia’s metals deposits, including most of our gold deposits, formed this way because North Africa and North America started colliding 400 million years ago and the two tectonic plates spent millions of years rubbing against each other.

However, faults that help create deposits can also make it difficult to find and extract the deposits because they allow blocks of rock to move relative to each other. This can cause deposits to be split, moving part of the deposit to a different, often hard-to-find, location. This is the case in Smithfield, where it is believed there may be more mineralization than the two deposits found to date.

A century and a half after lead was discovered at Smithfield, we are still trying to fully understand this complex but exciting site.

Smithfield is an example of how difficult it is to discover and develop mineral deposits. Only one in every 10,000 mineral exploration projects ends up being a mine.

Given how rare it is that a mineral deposit is economically viable, it is important that we develop them when we can, both for the materials they provide and the jobs and economic benefits they create.