tarbuttite

{{Infobox mineral | name = Tarbuttite | category = Phosphate minerals | boxwidth = | boxbgcolor = | image = Tarbuttite.JPG | imagesize = | caption = Tarbuttite from Broken Hill mine (Kabwe mine) in Central Province, Zambia | formula = Zn2(PO4)(OH) | IMAsymbol = Tbt | molweight = | strunz = 8.BB.35 | dana = 41.6.7.1 | system = Triclinic | class = Pinacoidal () (same H-M symbol) | symmetry = P | unit cell = a = 5.400 Å, b = 5.654 Å c = 6.465 Å, α = 102.51° β = 102.46°, γ = 86.50° Z = 2 | color = White, colorless, yellow, red, green, or brown | habit =Equant to short prismatic [001], sheaf-like aggregates, crusts, individual crystals rounded and deeply striated | twinning = | cleavage = Perfect on {010} | fracture = Irregular, uneven | tenacity = | mohs = 3.5 | luster = Vitreous, pearly on cleavages | polish = | refractive = nα = 1.660nβ = 1.705nγ = 1.713 | opticalprop = Biaxial (−) | birefringence = δ = 0.053 | 2V = 50° (measured) | dispersion = Weak, strong | pleochroism = | fluorescence= Non-fluorescent | absorption = | streak = White | gravity = 4.12; 4.19 (calc.) | density = 4.12 g/cm3 (measured) | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Transparent, translucent | other = | references = }}

Tarbuttite is a rare phosphate mineral with formula Zn2(PO4)(OH). It was discovered in 1907 in what is now Zambia and named for Percy Coventry Tarbutt.