In Canada 99% of uranium occurrences and 93% of properties producing uranium are on the Canadian Shield, almost all on the western and southern edges of it. Bancroft, known as the "Mineral Capital of Canada" is one of only a few places in the world and the only area in Canada where uranium is extracted from pegmatitic rock. The Canadian Shield is a broad region of Precambrian rock (pictured in shades of red) that encircles Hudson Bay. It spans eastern, northeastern, and east-central Canada and the upper midwestern United States. The key geological features in the Bancroft area relevant to uranium mining are three circular granitic complexes, each about 10 kilometers across. They are (from southwest to northeast): the Cheddar granite, the Cardiff plutonic complex and the Faraday granite. Cheddar granite The Cheddar complex is a circular double dome of granitic rock surrounded by paragneiss, para-amphibolite, and pyroxene granulite.
All these rocks contain younger granitic and syenitic intrusions. Cardiff plutonic complex Located northeast of the Cheddar granite, the Cardiff plutonic complex consists mainly of three southeast-dipping cylindrical sheet intrusions: the Centre Lake granite, the Monck Lake granite, and the Deer Lake syenite. They intrude metasedimentary rocks. Faraday granite Located northeast of the two other granitic complexes, the Faraday granite is a sheet of granite covered by gneisses and metagabbro. The Faraday granite sheet dips to the south and it is the southern edge of the Hastings Highland gneiss comple