Lanarkite

Lanarkite is a mineral, a form of lead sulfate with formula Pb₂(SO₄)O. It was originally found at Leadhills in the Scottish county of Lanarkshire, hence the name. It forms white or light green, acicular monoclinic prismatic crystals, usually microscopic in size. It is an oxidation product of galena.

Lanarkite
General
Category	Sulfate minerals
Formula	Pb2(SO4)O
IMA symbol	Lan[1]
Strunz classification	7.BD.40
Crystal system	Monoclinic
Crystal class	Prismatic (2/m) (same H-M symbol)
Space group	C2/m

In 2023, Lanarkite was used by Korean physicists in an attempt to make LK-99, a material evaluated for room-temperature superconductivity.^[2]