Marra Mamba Tiger Eye
Marra Mamba Tiger Eye is a 3 billion (yes, that is with a B) year old mineral found only in the Hamersley Ranges of Northwestern Australia. The colors here are quite true to reality, even though the flat two dimensional image does little justice to the wonderful apparent depth of the rock, nor the rolling flash of the tiger eye itself. The tiger eye component is fibrous riebeckite replaced by silica combined with yellow Geothite, and it is this silky luster of the fibrous bands that produced the magnificent reflections captured here. The remaining minerals of this banded iron resource are hematite (red), riebeckite (blue), goethite (yellow), along with hematite and magnetite (black). The green hues are from combinations of riebeckite and goethite. The sedimentary rocks were originally laid down approximately 3 billion years ago as sea floor, then slowly and gently metamorphosed by pressure and temperature, along with some mineral replacement that occurred with the coming of oxygen into the equation through the development of photosynthesizing organisms in the oceans some 2.7 billion years ago. This specimen was displayed by Donald Russel of Grass Valley, CA at the Tucson Gem and Mineral show.
February 9th, 2013
Viewed 136 Times - Last Visitor from Nürnberg, 02 - Germany on 04/03/2015 at 4:22 AM