Mineral relic
In mineralogy, a mineral relic is a mineral or mineral aggregate that shows the earlier stages of development of a rock even after a rock has undergone partial transformation. After crystallization , a rock can be subject to more or less complete mineral transformations due to changed pressure and temperature conditions, for example as a result of metamorphosis . Mineral relics, i.e. remnants of the original mineral stock, thus indicate the primary formation conditions of a rock.
One differentiates:
- stable relics: minerals or mineral aggregates that remain stable even with changed pressure and temperature conditions;
- unstable relics: minerals or mineral aggregates that become unstable under changed pressure and temperature conditions, but can still be partially preserved under certain circumstances;
- "Armored" or encrusted relics: minerals or mineral aggregates that have become unstable under changed pressure and temperature conditions can be encased or encrusted by stable minerals and thus trace the original crystal form .
Individual evidence
- ^ Author collective: Lexicon of Geosciences , Volume 4, Spektrum Akademischer Verlag, Berlin, Heidelberg 2001, ISBN 3-8274-0423-1 , pp. 306–307