Alum-(K)

Alum-(K) is a hydrous potassium aluminium sulfate mineral with formula KAl(SO4)2·12(H2O). It is the mineral form of potassium alum and is referred to as potassium alum in older sources. It is a member of the alum group. It occurs as colorless to white, soft isometric crystals and efflorescence coatings. Rare crystals are octahedral in form if occurring as precipitates from neutral water solution, but cubic in form if the solution is alkaline. Occurrences include Mount Vesuvius, Italy and Alum Cave, Sevier County, Tennessee.

Alum-(K)

Alum-(K) is a hydrous potassium aluminium sulfate mineral with formula KAl(SO4)2·12(H2O). It is the mineral form of potassium alum and is referred to as potassium alum in older sources. It is a member of the alum group. It occurs as colorless to white, soft isometric crystals and efflorescence coatings. Rare crystals are octahedral in form if occurring as precipitates from neutral water solution, but cubic in form if the solution is alkaline. Occurrences include Mount Vesuvius, Italy and Alum Cave, Sevier County, Tennessee.