Canada, Australia lead in uranium

Over the past 40 years, uranium has become one of the world’s most important energy minerals. It is used almost entirely for making electricity, though a small amount is used for the important task of producing medical isotopes.

Uranium averages about two parts per million of the earth’s crust. Traces of it occur almost everywhere. It is more abundant than gold, silver or mercury, roughly as abundant as tin, and slightly less abundant than cobalt, lead or molybdenum. Vast amounts of uranium also occur in the world’s oceans, but in much lower concentrations.

There are many uranium mines operating around the world, in about 20 countries, though more than two-thirds of world production comes from just 10 mines. Most of the uranium ore deposits being mined have average grades in excess of 0.1% of uranium. In the first phase of uranium mining, up to the 1960s, this would have been seen as a respectable grade, but today some Canadian mines have average uranium grades of up to 20%.

In Canada, uranium ores first attracted the public’s attention in the early 1930s, when the Eldorado Gold Mining Co. began recovering radium at Port Radium, N.W.T. A refinery to produce radium was built the following year at Port Hope, Ont., some 5,000 km away.

Exploration for uranium began in earnest in 1942, in response to a demand for defence purposes. By 1956, thousands of radioactive occurrences had been discovered, and three years later, 23 mines with 19 treatment plants were in operation in five districts. The main production centre was around Elliot Lake, Ont., but northern Saskatchewan hosted some plants. This first phase of Canadian uranium production peaked in 1959, when more than 12,000 tonnes of uranium were produced. The uranium generated more revenue than any other mineral exported from Canada that year.

The 1970s saw a revival in uranium exploration, mainly centred around the Athabasca Basin of northern Saskatchewan. The Rabbit Lake, Cluff Lake and Key Lake mines operated from 1975 until 1983. Exploration expenditures in the region peaked at this time, resulting in the discoveries of Midwest, McClean Lake and Cigar Lake. Then, in 1988, the newly formed Cameco Corp. discovered the massive McArthur River deposit. Today, Canada’s share of world uranium resources is about 15%, but the country produces about a third of all the uranium mined.

Uranium has been known to exist in Australia since the 1890s. In the 1930s, at Radium Hill in South Australia, uranium ores began to be mined in order to recover minute amounts of radium for medical purposes. As a result, a few hundred kilograms of uranium were also obtained, and these were used mostly to produce colours in glass and ceramics.

Australia has nearly double the recoverable uranium resources of Canada. The first major producer of uranium Down Under was the government-owned Rum Jungle project, in the Northern Territory, which operated from 1954 to 1971. It was closely followed by Radium Hill in South Australia, then Mary Kathleen in Queensland.

As a result of intensive exploration in the late 1960s Australia began to emerge as a potential major source of uranium for the world’s nuclear electricity production. At the beginning of the 1970s, a series of important discoveries was made, particularly in the Northern Territory. These include Ranger, Jabiluka and Nabarlek in the Northern Territory, Yeelirrie in Western Australia, and Olympic Dam (Roxby Downs) in South Australia. Today, Australia’s share of the world’s uranium resources is about 28%, and the country produces about 20% of the world’s mined uranium.

Other countries with major uranium deposits are Kazakstan, South Africa, Namibia, Brazil, Russia, and the U.S.