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Alteration
Title
Alteration
Subject
Rocks undergo mineralogical change at low pressures, produced by reactions with circulating fluids. The replacement of the original minerals in the rock tends to take place primarily along cracks and around the edges of grains, though whole mineral grains can be replaced. The decomposition of olivine to serpentine is a common example of alteration.
Description
Common alteration minerals include clays for plagioclase, serpentine for olivine, and chlorite for ferromagnesian minerals such as biotite.
Collection
Citation
“Alteration,” 1A Collections, accessed April 9, 2024, https://wserv3.esc.cam.ac.uk/p1acollections/items/show/170.