Tarbuttite
Chemical Formula	Zn2(PO4)(OH)
Species	Phosphates
Crystal System	Triclinic
Mohs Scale	3
Specific Gravity	4.2
Color	White, colorless, yellow, red, green, or brown
Streak	White
Luster	Vitreous, Pearly
Refractive Index	n = 1.660 n = 1.705 n = 1.713
Diaphaneity	Transparent, Translucent
Cleavage	PerfectOn , perfect.
Fracture	Irregular/Uneven
Crystal Habit：Crystals equant to short prismatic. Commonly found as sheaf-like aggregates or as crusts. Individual crystals commonly rounded and deeply striated.