Aeschynite
Aeschynite-(Y) is a ytrrium that is rareREE – rare earth element) mineral that is extremely rare as being a gemstone. It is bought at several locations throughout the world but the source that is primary the type locality; Iveland, Aust-Agder, Norway. It is closely related to Aeschynite-Ce (Cerium) and Aeschynite-Nd (Neodymium), both of which are slightly radioactive.
Rare earth oxides such as Aeschynite kind from elements that are often leftover from other minerals. Other planet that is rare such as Fergusonite-(Ce), Samarskite-(Y) and Euxenite-(Y) have actually extremely similar properties to Aeschynite and are often associated with each other as they are hard to tell apart from one another. Also the oxide that is common Rutile, is nearly indistinguishable from these uncommon earth oxides without chemical tests when Rutile is situated in its massive form.
Aeschynite-(Y) is found at a number of localities around the world including localities which are numerous Norway, including: at Urstad, on Hidra (Hitterö) Island; Sätersdalen; at Kåbuland, Mölland, and Birkeland; near Arendal, Mörefjär, and Salterö; at Frikstad. In Russia, at Miass, within the Ilmen Mountains, Southern Ural Mountains. In Switzerland, from Piz Lucendro, near the St. Gotthard Pass, on Pizzo Rotondo, Val Bedretto, and Val Nalps, Tavetsch, Graub¨unden; and somewhere else. In Italy, on Pizzo Cervandone, Alpe Devero, Val d’Aosta, Piedmont. At Böckstein, near Bad Gestein, Austria. From Tongafeno, Ambedabao, Ambohitromby, near Ambatofotsy, Tomboarivo, and other localities in Madagascar. From the Embabaan district, Swaziland. In america at Clora May Mine (Mina Blanca; Clara May Lode), Trout Creek Pass pegmatite District, Buena Vista, Chaffee Co., Colorado. A number of other localities which are less-well-defined known.
| Chemical Formula: | (Y,Ca,Fe,Th)(Ti,Nb)2(O,OH)6 |
| Yttrium Calcium Iron Titanium Niobium Oxide Hydroxide | |
| Molecular Weight: | 274.97 gm |
| Composition: | Calcium | 4.37 % | Ca | 6.12 % | CaO |
| Yttrium | 19.40 % | Y | 24.64 % | Y2O3 | |
| Titanium | 30.47 % | Ti | 50.84 % | TiO2 | |
| Niobium | 8.45 % | Nb | 12.08 % | Nb2O5 | |
| Iron | 2.03 % | Fe | 2.61 % | FeO | |
| Hydrogen | 0.37 % | H | 3.28 % | H2O | |
| Oxygen | 34.91 % | O | |||
| 100.00 % | 100.00 % | = TOTAL OXIDE |
| Crystallography: | Orthorhombic – Dipyramidal |
| Crystal Habit: | Crystals, to 10 cm, commonly tabular, less commonly prismatic, also granular. |
| Twinning: | None |
| Cleavage: | Perfect on {100}, {010} and {001} |
| Fracture: | Irregular/Uneven |
| Tenacity: | Brittle |
| Moh’s Hardness: | 5.0 – 6.0 |
| Density: | 4.82 – 4.93 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Not Radioactive |
| Other: | Magnetic |
| Color: | Black, Brownish black, Brown, Brownish Yellow, pale Yellow, Yellow-Orange, pale Greenish Yellow |
| Transparency: | Opaque to Semi-Transparent |
| Luster: | Resinous, Waxy, Pearly, Sub-Metallic, Submetallic to Pearly on crystal faces, Resinous to Waxy on fracture surfaces. |
| Refractive Index: | 2.19 – 2.50 Biaxial ( + ) |
| Birefringence: | 0.150 – 0.220 |
| Dispersion: | Strong; r > v |
| Pleochroism: | None |
