A few of the natural resources in the Canadian Shield, Canada's largest physiographic region, include iron, copper and gold. The shield is made up of igneous and metamorphic rock that are among the oldest in North America, with some identified as being over 2 billion years old.
The Canadian Shield covers around 4.8 million square kilometers, just under 3 million square miles, and stretches from Alberta all the way east to Newfoundland and north toward Greenland. It makes up almost two-thirds of the province of Ontario. It is a major part of Canada's geographic and cultural history, with the layout of the waterways during glaciations even responsible for where European and native people settled.
The Shield was the first area that rose above sea level in North America, and a depression caused by continental ice sheets is responsible for creating the Hudson Bay, an important part of Canada's early trading history. The Canadian Shield has been changed by erosion and the elements over the years and is currently home to Precambrian rocks that have been there for more than 570 million years. The rocks include marbles, granites, basalts, schists and diorites. The Canadian Shield is a rich source of mineral resources, including uranium, nickel, zinc and silver.