Humite
Humite could be the member that is principal of Humite band of minerals that includes Chondrodite, Clinohumite, Humite, and Norbergite. It is a Nesosilicates category, with the formulae of (Mg, Fe2+)7(SiO4)3(F, OH)2 (Magnesium Iron Silicate Fluoride Hydroxide). Humite is a mineral that is pretty rare can be found in contact metamorphic dolomitic limestones as small prismatic crystals. Humite crystals are rarely enough that is clean faceting. One source that is current of treasure quality crystals is the Minh Tien Mine, Luc Yen, Yenbai (Yen Bai) Province, Vietnam.
Other sources of Humite are Monte Somma and Vesuvius, Campania, Italy; Lohja, Sillböle, and Hermala, Finland; the Norberg area, and also at the Ladu mine, Persberg, Värmland, Sweden; at Anzahamazonono, Madagascar; Sorfinnset, Glomfjord, Norway; Llanos de Juanar, Málaga Province, Spain; the Tilly Foster mine, Brewster, Putnam County, NY, and at Franklin, Sussex County, New Jersey, USA.
| Category: | Nesosilicates |
| Chemical Formula: | (Mg, Fe2+)7(SiO4)3(F, OH)2 |
| Magnesium Iron Silicate Fluoride Hydroxide | |
| Molecular Weight: | 538.58 gm |
| Composition: | Magnesium | 23.69 % | Mg | 39.29 % | MgO |
| Iron | 18.15 % | Fe | 23.34 % | FeO | |
| Silicon | 15.64 % | Si | 33.47 % | SiO2 | |
| Hydrogen | 0.09 % | H | 0.84 % | H2O | |
| Oxygen | 37.13 % | O | |||
| Fluorine | 5.29 % | F | 5.29 % | F | |
| – | – % | F | -2.23 % | -O=F2 | |
| 100.00 % | 100.00 % | = TOTAL OXIDE |
| Crystallography: | Orthorhombic – Dipyramidal |
| Crystal Habit: | Crystals typically highly modifeed, to 1 cm; granular |
| Twinning: | None |
| Cleavage: | {100} Poor |
| Fracture: | Uneven to Subconchoidal |
| Tenacity: | Brittle |
| Moh’s Hardness: | 6.0 |
| Density: | 3.20 – 3.32 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Not Radioactive |
| Color: | White, Yellow, dark Orange, Brown; Colorless to Yellow-Brown in thin section |
| Transparency: | Transparent to Translucent |
| Luster: | Vitreous |
| Refractive Index: | 1.607 – 1.675 Biaxial (+) |
| Birefringence: | 0.032 |
| Dispersion: | Weak; r > v |
