| Germanite | |
| Category: | Sulfide mineral |
| Formula: | Cu26Ge4Fe4S32[1] |
| Imasymbol: | Ger[2] |
| Strunz: | 2.CB.30 |
| Dana: | 2.9.4.2 |
| System: | Isometric |
| Class: | Hextetrahedral (3m) H-M symbol: (3m) |
| Symmetry: | P3n |
| Color: | Reddish grey tarnishing to dark brown |
| Habit: | Usually massive; rarely as minute cubic crystals |
| Cleavage: | None |
| Tenacity: | Brittle |
| Mohs: | 4 |
| Luster: | Metallic |
| Streak: | Dark grey to black |
| Gravity: | 4.4 to 4.6 |
| Diaphaneity: | Opaque |
| Other: | Cell data: a = 10.585 Å Z = 1 |
| References: | [3] [4] |
Germanite is a rare copper iron germanium sulfide mineral, Cu26Fe4Ge4S32. It was first discovered in 1922, and named for its germanium content. It is only a minor source of this important semiconductor element, which is mainly derived from the processing of the zinc sulfide mineral sphalerite.[5] Germanite contains gallium, zinc, molybdenum, arsenic, and vanadium as impurities.
Its type locality is the Tsumeb Mine in Namibia where it occurs in a hydrothermal polymetallic ore deposit in dolomite in association with renierite, pyrite, tennantite, enargite, galena, sphalerite, digenite, bornite and chalcopyrite.[4] It has also been reported from Argentina, Armenia, Bulgaria, Cuba, Democratic Republic of Congo (Zaire), Finland, France, Greece, Japan, Republic of Congo (Brazzaville), Russia and the United States.[6]
| X-Ray Powder Diffraction[7] | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| d spacing | 3.05 | 2.65 | 1.87 | 1.60 | 1.32 | 1.21 | 1.08 | 1.02 | |
| relative intensity | 10 | 1 | 7 | 4 | 1 | 2 | 2 | 1 |