Yava Mine

It is not hard to figure out how the community of Silver Mine, Cape Breton County, got its name! Silver was discovered there in 1881 but little is known about the find.

The area was again explored in 1918, but for lead, not silver. Eight prospecting pits were dug, the deepest being 17 feet. The ore, which occurred in limestone, showed mineralization for a distance of four miles. Tests of the ore showed that it contained 2-64 ounces of silver per ton and 4-38% lead.

According to a report done in the early 1960s, local residents said the ore was extracted in 1918 from a creek bed 2000 feet southeast of Silver Mine, which had to be diverted for mining operations. The ore was shipped to England. However, mining work was continually hampered by flooding and had to be given up. The creek returned to its original course and the only evidence of the short-lived mine was a depression in the creek and a few timbers.

The area was explored on and off for decades for galena, an ore of lead (meaning lead is extracted from galena).

Exploration really picked up in the 1960s a short distance north of the 1918 workings. Various exploration drilling programs were done, and a 50-ton bulk sample of mineralized sandstone was extracted and shipped to the Ontario Research Foundation mill for testing.

Phelps Dodge Corporation of Canada, Talisman Mines and Gunnex Ltd. jointly incorporated Yava Mines Ltd. in 1964 to advance the Yava lead mine project. Between 1972-75, Barymin Exploration Ltd. bought Gunnex Ltd. and the shares of Yava Mines Ltd. from Phelps Dodge and Talisman, giving Barymin 100% ownership of Yava.

At this point, bad luck for one company became good luck for another. During the early 1970s, the Kaiser celestite mine operated at Lake Enon, 11 kilometres from the Yava site. However, the celestite mine shut down in 1976 due to difficult market conditions. That meant its mill was available for purchase, so Yava Mines bought it to process the ore from its mine.

The Yava underground lead mine opened in June 1979. In its first two years, the mine extracted 388,000 tonnes of ore with a head grade of 4.69% lead. Concentrates were shipped via Sydney to a West German company called Metallgesellschaft AG, which was formerly one of Germany’s largest industrial conglomerates. Founded in 1881, it owned over 250 companies in various sectors, including mining, chemicals and finance and engineering.

Unfortunately, Yava declared bankruptcy in fall 1981 due to financial challenges and low global lead prices.

The Nova Scotia Department of Mines did additional exploration drilling in 1986-87 and found that the site also has potential to produce zinc, a critical mineral used in things like electric vehicles and wind turbines today.

An investigation done in 1989 found that the Yava deposit has potential to be extracted with solution mining (aka in-situ leaching).

Conventional mining means removing mineralized rock (ore) from the ground, breaking it up and treating it to remove the minerals being sought.

In solution mining, the ore is left in the ground and the minerals are extracted by dissolving them in liquid and pumping the solution to the surface where the minerals can be recovered. This results in less disturbance at surface and produces basically no tailings or waste rock.

Solution mining has been done in Nova Scotia since 1947 in Nappan, Cumberland County, where a world-class salt deposit has been extracted using the process. Hot water is pumped into drill holes under pressure and the resulting salt brine is pumped back out, then sent through a settling and evaporation process at the surface to produce a high-purity salt.

While there are advantages to solution mining, it can only be done for some minerals and in deposits that have the right conditions. For example, the deposit needs to be permeable (able to absorb the liquid) so the minerals can be dissolved, but located such that the process will not interact with groundwater (i.e. it is often done below groundwater and/or where the deposit is surrounded by other rock that is impermeable).