a mineral, a hydrous sulfate of potassium and aluminum, KAl3(SO4)2(OH)6, commonly occurring in fine-grained masses.
- Also called al·um·stone [al-uhm-stohn]. /ˈæl əmˌstoʊn/.
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How to use alunite in a sentence
alunite, al′un-īt, n. a mineral consisting of common alum together with normal hydrate of aluminium.
Alum-rock, or alum-stone, is a species of impure alunite, and is not of very common occurrence.
In the Goldfield camp (p. 230) the ores are closely associated with alunite in such a manner as to suggest a common origin.
alunite is a potassium-aluminum sulphate, which differs from sericite in that sulphur takes the place of silicon.
alunite occurs as veins and replacement deposits, often in igneous associations, and is supposed to be of igneous source.
British Dictionary definitions for alunite
a white, grey, or reddish mineral consisting of hydrated aluminium sulphate. It occurs in volcanic igneous rocks and is a source of potassium and aluminium compounds. Formula: KAl 3 (SO 4) 2 (OH) 6
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