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Mineralati

Minerals

Halotrichite

halotrichite

Fe²⁺Al2(SO4)4·22H2O

Halotrichite: Mineral information, data and localities.

Halotrichite: Mineral information, data and localities. — via www.mindat.org · Source

Overview

Halotrichite, also known as feather alum, is a highly hydrated sulfate of aluminium and iron. Its chemical formula is FeAl2(SO4)4·22H2O. It forms fibrous monoclinic crystals. The crystals are water-soluble. It is formed by the weathering and decomposition of pyrite commonly near or in volcanic vents. The locations of natural occurrences include: the Atacama Desert, Chile; Dresden in Saxony, Germany; San Juan County, Utah; Iceland; Idrija, Slovenia; and Mont Saint-Hilaire, Canada. The name is from Latin: halotrichum for salt hair which accurately describes the precipitate/evaporite mineral.

Gallery

Identification characteristics

  • Mohs hardness 1.5

Scientific references

  1. Halotrichite — Wikidata. https://www.wikidata.org/wiki/Q417278 Link
  2. Halotrichite — Wikipedia. https://en.wikipedia.org/wiki/Halotrichite Link