Paramorphism

paramorphism

[¦par·ə′mȯr‚fiz·əm]

(mineralogy)

The property of a mineral whose internal structure has changed without change in composition or external form. Formerly known as allomorphism.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Paramorphism

 

a type of pseudomorphism that involves the polymorphous alteration of a high-temperature form of a mineral to a low-temperature form. With paramorphism there is a rearrangement in the crystalline structure of the mineral without a change in chemical composition; the external shape of the original crystal is also preserved. Examples of paramorphs are hexagonal α-quartz after trigonal β-quartz, rhombic sulfur after monoclinic sulfur, trigonal calcite after rhombic aragonite, and cubic pyrite after rhombic marcasite.

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