Bismuthinite (incl.)
Bismuthinite can be an attractive mineral for collectors when is in the form of steel gray prismatic crystals radiating outward from a common point. These radiating groups of crystals can be very similar to specimens of Stibnite and are difficult to distinguish from this closely related mineral. Bismuthinite is rarely mentioned in gem circles except maybe as attractive inclusions in Quartz. More specifically, in Rose Quartz from a source in Madagascar.
Distribution of Bismuthinite is widespread. From the Llallagua, Huanuni, Tazna, and Chorolque districts, Potosí, Bolivia. From Guanajuato, Mexico. In the USA, large crystals at the Victoria mine, Dolly Varden district, Elko County; in a number of mines in the Goldfield district, Esmeralda County, and elsewhere in Nevada. From Moravicza and Baita (Rézbánya), Romania. At Schneeberg and Altenberg, Saxony, Germany. From a number of mines in Cornwall, England. In the Mt. Biggenden mine, Queensland, Australia. At Fefena, Madagascar. Exceptional crystals from Spind, Farsum, Norway.
| Chemical Formula: | Bi2S3 |
| Bismuth Sulfide | |
| Molecular Weight: | 514.16 gm |
| Composition: | Bismuth | 8129 % | Bi | ||
| Sulfur | 18.71 % | S | |||
| 100.00 % |
| Crystallography: | Orthorhombic – Dipyramidal |
| Crystal Habit: | Crystals, up to 12 cm, stout prismatic to acicular, elongated and striated || [001]. Commonly massive with foliated or fibrous texture. |
| Twinning: | None |
| Cleavage: | Perfect and Easy on {010}, Imperfect on {100} and {110} |
| Fracture: | Sectile |
| Tenacity: | Flexible, somewhat Sectile |
| Moh’s Hardness: | 2.0 – 2.5 |
| Density: | 6.78 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Not Radioactive |
| erties | |
| Color: | Lead-Gray to tin-White, with a Yellowish or iridescent tarnish |
| Transparency: | Opaque |
| Luster: | Metallic |
| Refractive Index: | R1–R2: (400) 35.7–46.2, (420) 36.4–47.2, (440) 37.2–47.9, (460) 37.7–48.3, (480) 37.7–48.8, (500) 37.6–49.4, (520) 37.3–49.6, (540) 37.1–49.1, (560) 36.9–48.7, (580) 36.8–48.3, (600) 36.6–47.8, (620) 36.4–47.3, (640) 36.3–46.8, (660) 36.1–46.3, (680) 36.0–45.8, (700) 35.9–45.4 |
| Birefringence: | 0.000 |
| Dispersion: | n/a |
| Pleochroism: | None |
| Anisotrophism: | Strong, especially in oil |
