Lanarkite
Chemical Formula	Pb2(SO4)O
Species	Sulfates
Crystal System	Monoclinic
Mohs Scale	2
Specific Gravity	6.4-6.8
Color	Greenish white, greyish-white, more rarely pale-yellow; colourless in transmitted light.
Streak	White
Luster	Adamantine, Resinous, Pearly
Refractive Index	n = 1.928 n = 2.007 n = 2.036
Diaphaneity	Transparent, Translucent
Cleavage	PerfectPerfect on , imperfect on and ; also on .
Fracture	Splintery
Crystal Habit：Crystals prismatic, elongated parallel , typically microscopic and in clusters or sprays; massive.
Geological Setting：A secondary mineral of lead deposits, typically formed by the alteration of galena or other secondary minerals formed from galena.