Niedermayrite is a rare hydrated copper cadmium sulfate hydroxide mineral with formula: Cu4Cd(SO4)2(OH)6·4H2O. It crystallizes in the monoclinic system and occurs as encrustations and well formed vitreous blue-green prismatic crystals. It has a specific gravity of 3.36.
{{Infobox mineral | name = Niedermayrite | image = Niedermayrite-382305.jpg | alt = | caption = | category = Sulfate mineral | formula = Cu4Cd(SO4)2(OH)6·4H2O | IMAsymbol = Ndm | molweight = | strunz = 7.DD.30 | system = Monoclinic | class = Prismatic (2/m) (same H-M symbol) | symmetry = P21/m | unit cell = a = 5.543(1), b = 21.995(4) c = 6.079(1) [Å]; β = 92.04(3)°; Z = 2 | color = Bluish green | colour = | habit = Platy euhedral crystals and as green crusts | twinning = | cleavage = Perfect on {010} | fracture = | tenacity = Brittle | mohs = | luster = Vitreous | streak = White | diaphaneity = Transparent | gravity = 3.292 | density = | polish = | opticalprop = Biaxial (-) | refractive = nα = 1.599 - 1.619 nβ = 1.642 nγ = 1.661 | birefringence = δ = 0.062 | pleochroism = | 2V = Measured: 84° | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | prop1 = | prop1text = | references = }}
Niedermayrite is a rare hydrated copper cadmium sulfate hydroxide mineral with formula: Cu4Cd(SO4)2(OH)6·4H2O. It crystallizes in the monoclinic system and occurs as encrustations and well formed vitreous blue-green prismatic crystals. It has a specific gravity of 3.36.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).