Attawapiskat kimberlite field mine was expected to produce of diamonds a year. Attawapiskat kimberlite field The Attawapiskat kimberlite field is a field of kimberlite pipes located astride the Attawapiskat River in the Hudson Bay Lowlands, in Northern Ontario, Canada. It is thought to have formed about 180 million years ago in the Jurassic period when the North American Plate moved westward over a centre of upwelling magma called the New England hotspot, also referred to as the Great Meteor hotspot. Since June 26, 2008, the De Beers open pit Victor Diamond Mine has been in operation mining two pipes in the field at
Volcanic rock that after the mineral had crystallized it was partly again dissolved or corroded at some period before the matrix solidified. Corroded phenocrysts of biotite and hornblende are very common in some lavas; they are surrounded by black rims of magnetite mixed with pale green augite. The hornblende or biotite substance has proved unstable at a certain stage of consolidation, and has been replaced by a paramorph of augite and magnetite, which may partially or completely substitute for the original crystal but still retains its characteristic outlines. Volcanic rock Volcanic rock (often shortened to volcanics in scientific contexts) is a rock