| Niedermayrite | |
| Category: | Sulfate mineral |
| Formula: | Cu4Cd(SO4)2(OH)6·4H2O |
| Imasymbol: | Ndm[1] |
| 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 |
| Habit: | Platy euhedral crystals and as green crusts |
| Cleavage: | Perfect on |
| Tenacity: | Brittle |
| Luster: | Vitreous |
| Streak: | White |
| Diaphaneity: | Transparent |
| Gravity: | 3.292 |
| Opticalprop: | Biaxial (-) |
| Refractive: | nα = 1.599 - 1.619 nβ = 1.642 nγ = 1.661 |
| Birefringence: | δ = 0.062 |
| 2V: | Measured: 84° |
| References: | [2] [3] |
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.
Niedermayrite was named for Gerhard Niedermayr (born 1941), an Austrian mineralogist. It was first described in 1998 from a mine in the Lavrion District, Attica, Greece. It is also reported from the Ophir District, Tooele County, Utah.[2] The environment is in brecciated marble. The cadmium dominant analogue of campigliaite.