Idiomorphism


Also found in: Dictionary.
Related to Idiomorphism: Hypidiomorphic, isomorphism
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Idiomorphism

 

the ability of grains of minerals during their crystallization in rocks or ore bodies to assume the form of well-faceted crystals typical of these minerals. Minerals that crystallize in the early stage of the formation of a rock or ore from astatic media (for example, melts or water solutions) usually have the most marked idiomorphism. The degree of idio-morphism is also determined by the crystallizing capability of the substance, and for this reason minerals that recrystallize in a solid medium or that have formed in the late stages of the crystallization of the minerals of a rock or ore body can also be idiomorphic. Common idiomorphic minerals in rocks include feldspars, augites, amphiboles, quartz, and nepheline; among the ores, pyrite and arsenopyrite are often idiomorphic.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.