Simpsonite

Facts

Chemical formula

Al₄Ta₃O₁₃(OH)

Crystal system

Trigonal

Mohs hardness

7.5

Elements in formula

Aluminium, Tantalum, Oxygen, Hydrogen

Number of elements

4

IMA status

Grandfathered

Named after

Edward Sydney Simpson

Sources: Wikidata (CC0), IMA list of minerals via Wikidata · Wikidata Q408497