Ekaterinburg-Beresov, Russia/ekatberezov770
Previous | Home | NextThis is typical platinum ore taken from the Nizhniy Tagil region -- platinum-group elements are typically found as tiny inclusions in seams of the chromite (darker veins) imbedded in dunite (lighter brown matrix). Chromite is FeCr2O4; dunite is a dense igneous rock with a sugary texture consisting mainly of olivine (magnesium iron silicate). Dunite is formed by the up-thrusting of deep mantle rock during continental collisions. The Urals were formed 250-300 million years ago when the supercontinent islands Siberia and Baltica collided. Dunite is named for its dun color (grayish-brown). For size, a 1-ruble coin is included (20.5 mm in diameter; about the size of a nickel). Courtesy, BRGM- A. Genna.
