Halotrichite

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Notion

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Science and technology

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What Wikipedia says

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.

Excerpt from the Wikipedia article “Halotrichite”, under the CC BY-SA 4.0 license. Read the article on Wikipedia

Image: Robert M. Lavinsky, CC BY-SA 3.0, via Wikimedia Commons.