Andradite (Garnet)
Andradite is a member that is famous the Garnet musical organisation of minerals that includes Almandine, Andradite, Grossular, Pyrope, Spessartine and Uvarovite. Andradite’s different colours contain yellow, greenish yellowish to emerald-green, dark green, brown, brownish Red, brownish Yellow; grayish-black coloured and black. Andradite is found in several varieties Demantoid that is including and Topazolite. Demantoids will function as the variety that is rich is green by chromium and tend to be the absolute most commonly known about the Andradites. Demantoid is named from your message that is archaic is German” which means “diamond” in allusion to its high brilliance resembling that of Diamond. Melanites are typically black and contain about 1-5% titanium oxide. Melanite is termed from the Greek word “melan”, meaning black coloured. Topazolites are actually an unusual yellowish to the variety that is golden is yellowish for its resemblance in colour and clarity to Topaz.
Andradite was called in 1868 by USA geologist and mineralogist James Dwight Dana (1813-1895) in honour of José Bonifácio de Andrada e Silva (1763-1838), Brazilian mineralogist who first described the mineral. José Bonifácio had been a mineralogist, naturalist, poet and professor of geology. He named and discovered four mineral that is new: Cryolite, Petalite, Scapolite and Spodumene. He also named these eight mineral varieties (or synonyms): Acanthite (syn. of Epidote), Allochroite (syn. of Andradite), Aphrizite (a variety that is black colored of), Coccolite (syn. of Diopside), Ichtyophtalme (syn. of Apophyllite), Indicolite (blue number of Tourmaline),Salite (variety of pyroxene) and Wernerite. José Bonifácio named most of the minerals which he discovered with clinical names derived from Greek words, with the exception of Wernerite. Wernerite was referred to as in 1800 by José Bonifácio to honour Abraham Gottlob Werner (1749-1817), a professor of mining and mineralogy at the Freiberg Mining Academy, Germany. Werner finished up as an instructor that is influential his some ideas shaped thought that is early geological. He has been called the “father of German geology”. September in 1792, José Bonifácio went along to Germany to go to the Frieberg Mining Academy to examine under Werner.
Circulation: widespread; fine examples from; in Italy, at Frascati, Alban Hills, Lazio; the Val Malenco, Lombardy; the Ala Valley, Piedmont; and Larcinaz, Val d’Aosta. At Dognecea (Dognaczka) and Oravi» ta (Oravicza), Banat, Romania. From Once defier, Romania (Vaskö, Hungary). At Zermatt, Valais, Switzerland. From Arendal, Norway. Into the Wessels mine, near Kuruman, Cape Province, South Africa. In Russia, gem crystals from the Bobrovka River, Nizhni Tagil region, additionally the Desserts district, Ural Mountains; at Sineretschenskoje, north of Vladivostock. Within the United States Of America, from Stanley Butte, Graham County, Arizona; on Garnet Hill, Calaveras County, and around the Gem mine, San Benito County, Ca; at Franklin and Sterling Hill, Sussex County, New Jersey; from Magnet Cove, Hot Spring County, Arkansas; and on Prince of Wales Island, Alaska. In Mexico, found near Charco de Peña, about 75 kilometres east of Lázaro Cárdenas, Chihuahua.
| Category: | Garnet group |
| Chemical Formula: | Ca3Fe23+(SiO4)3 |
| Calcium Iron Silicate | |
| Molecular Weight: | 508.18 gm |
| Composition: | Calcium | 23.66 % | Ca | 33.11 % | CaO |
| Iron | 21.98 % | Fe | 28.28 % | FeO | |
| Silicon | 16.58 % | Si | 35.47 % | SiO2 | |
| Oxygen | 37.78 % | O | |||
| 100.00 % | 96.85 % | = TOTAL OXIDE |
| Crystallography: | Isometric – Hexoctahedral |
| Crystal Habit: | Commonly well-crystallized dodecahedra, trapezohedra, or combinations, to 5 cm. Also granular to massive. |
| Twinning: | None |
| Cleavage: | None |
| Fracture: | Irregular/Uneven to Conchoidal |
| Tenacity: | Brittle |
| Moh’s Hardness: | 6.5 – 7.0 |
| Density: | 3.70 – 4.10 (g/cm3) |
| Luminescence: | Not Fluorescest |
| Radioactivity: | Not Radioactive |
| Colour: | Yellow, Greenish Yellow to Emerald-Green, dark Green; Brown, Brownish Red, Brownish Yellow; Grayish Black, Black; may be sectored. |
| Transparency: | Transparent to Translucent |
| Lustre: | Adamantine to Resinous, Dull |
| Refractive Index: | 1.887 Isotropic |
| Birefringence: | 0.000 (Isotropic minerals have no birefringence) |
| Dispersion: | 0.057 (large) |
| Pleochroism: | None |
| Anisotrophism: |
Typically weakly anisotropic |
