An Unusual Deposit of Volcanic Ash

摘要

Volcanic ash (very boring and unremarkable looking stuff) is a mixture of a variety of minerals that reflect the composition of the magma from which it originated. Volcanic ash of a single mineral composition is pretty rare. Such a deposit exists near Panaca, Lincoln Co., Nevada. XRD and EDS/ SEM analyses have shown the ash to be an intermediate phase of Alkali Feldspar between Sanidine, (K,Na)AlSi3O8, and Orthoclase/Microcline, KAlSi3O8, in composition.