macphersonite

{{infobox mineral | name = Macphersonite | category = Carbonate mineral | boxwidth =330px | boxbgcolor = | image = Macphersonite.jpg | imagesize = | alt = | caption = | formula = Pb4(SO4)(CO3)2 (OH)2 | IMAsymbol = Mps | molweight = 1,078.90 g/mol | strunz = 5.BF.40 | dana = 17.01.04.01 | system = Orthorhombic | class = Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) | symmetry = Pcab | unit cell = a = 10.37 Å, b = 23.10 Å, c = 9.25 Å, β = 106.43°; Z = 8 | color = White, pale amber, colorless | habit = Pseudo hexagonal, tabular | twinning = Polysynthetic, lamellar, contact | cleavage = Perfect on {010} | fracture = Uneven | tenacity = | mohs = 2.5 - 3 | luster = Adamantine, otherwise resinous | streak = White | gravity = 6.50 | density = | fluorescence= A very strong and vivid yellow | opticalprop = Biaxial (-) | refractive = nα = 1.870 nβ = 2.000 nγ = 2.010 | birefringence = δ = 0.140 | pleochroism = | 2V = 35-36° | dispersion = r > v | absorption = | melt = | fusibility = | diagnostic = | solubility = | other = Polymorph of leadhillite and susannite | references = }}

Macphersonite, Pb4(SO4)(CO3)2 (OH)2, is a carbonate mineral that is trimorphous with leadhillite and susannite. Macphersonite is generally white, colorless, or a pale amber in color and has a white streak. It crystallizes in the orthorhombic system with a space group of Pcab. It is fairly soft mineral that has a high specific gravity.