Diavik Diamond Mine This is the largest diamond ever found in North America. Diavik Diamond Mine The Diavik Diamond Mine is a diamond mine in the North Slave Region of the Northwest Territories, Canada, about northeast of Yellowknife. Diavik Diamond Mine is an industrial complex set in a remote, sub-Arctic landscape. It consists of four kimberlite pipes associated with the Lac de Gras kimberlite field and is located on an island in Lac de Gras and is informally called East Island. It is about south of the Arctic Circle. In the 2015 satellite image below, one can see the two main open pits,
Permafrost down to . Discontinuous permafrost is often further divided into "extensive discontinuous permafrost", where permafrost covers between 50 and 90 percent of the landscape and is usually found in areas with mean annual temperatures between , and "sporadic permafrost", where permafrost cover is less than 50 percent of the landscape and typically occurs at mean annual temperatures between . In soil science, the sporadic permafrost zone is abbreviated SPZ and the extensive discontinuous permafrost zone DPZ. Exceptions occur in "un-glaciated" Siberia and Alaska where the present depth of permafrost is a relic of climatic conditions during glacial ages where winters