Enstatite

Transmitted Light, No Polarizing Filters

Definition/Function:

Enstatite is one of the orthopyroxenes (Mg,Fe²⁺SiO₃).

Significance in the Environment:

Characteristic Features:

Enstatite with about 15% iron is an orthorhombic crystal with gamma green and alpha pink pleochroism. the crystals tend to elongate along gamma so this refractive index is generally easy to measure and is a good indicator of the iron content in this mineral. The gamma refractive index ranges from 1.658 to 1.788. The alpha refractive index ranges from 1.650 to 1.768 and the beta refractive index from 1.653 to 1.770. Enstatite can be distinguished from andalusite by andalusite's tendency to elongate along alpha rather than gamma.

Associated Particles:

References:

Deer, W. A., R. A. Howie, and J. Zussman, AN INTRODCUTION TO THE ROCK-FORMING MINERALS, ISBN 0-582-30094-0, pp. 155-165, 1992.