On the Silver Trail

Cobalt is a crucial resource for the twenty-first century. Frequently found alongside ­silver in geological formations, it is one of the most sought-after minerals in the world, with all kinds of uses in our digital age, including an important role in the lithium-ion batteries that power smartphones and electric vehicles. Cobalt is also the name of a small town in the Temagami region of northern Ontario, where in the early twentieth century silver deposits drove an explosive growth in the Canadian mining industry. Toronto — a five-hour drive south — became the financial centre of Canada thanks to Cobalt’s riches. Today the community is merely one of many shrunken mining towns dotted across a scrubby landscape, far from the urban centres that hug the border with the United States.

The contrast between the prosperity of those southern cities and the rundown state of Cobalt is not pretty. It is hard to believe that once this place hustled and bustled with the...