Attawapiskat kimberlite field 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 , about west of the community of Attawapiskat. The
Volcanic rock grained matrix. Volcanic rocks often have a vesicular texture caused by voids left by volatiles trapped in the molten lava. Pumice is a highly vesicular rock produced in explosive volcanic eruptions. Most modern petrologists classify igneous rocks, including volcanic rocks, by their chemistry when dealing with their origin. The fact that different mineralogies and textures may be developed from the same initial magmas has led petrologists to rely heavily on chemistry to look at a volcanic rock's origin. The chemistry of volcanic rocks is dependent on two things: the initial composition of the primary magma and the subsequent differentiation. Differentiation