Danalite
Danalite is a beryllium that is unusual sulfide mineral that is clearly a member of the Helvine Group of minerals which also includes Genthelvite, Helvine and Tugtupite. Danalite had been very first described in 1866 from a deposite in Essex County, Massachusettes, USA. Danalite are located in colors of yellowish, pink, reddish brown or red but seldom crystalized and a lot of frequently found as red to pink masses that are opaque stone. Danalite is translucent to semi-transparent with vitreous to luster that is greasy a Mohs hardness of 5.5 – 6.0. Faceted gems have become rare and typically really small.
Danalite had been named in 1866 by Harvard chemist and mineralogist Josiah Parsons Cooke Jr. (1827-1894) to honor American geologist, mineralogist, volcanologist, and zoologist James Dwight Dana (1813-1895). Dana is credited with naming more than 100 minerals. He also published significantly more than 200 titles of publications, manuscripts and papers beginning in 1835 with a paper on the conditions of Mount Vesuvius. Dana’s best understood publications had been his System of Mineralogy (1837), Manual of Mineralogy (1848) and handbook of Geology (1863). These books are extremely distinguished in the fields of geology and mineralogy. The Manual of Mineralogy became a university that is standard and happens to be continuously revised and updated. The version that is 23rd now in print underneath the title Manual of Mineral Science (Manual of Mineralogy) (2007). Dana’s System of Mineralogy has also been continuously revised and updated utilizing the edition that is 8th published in 1997 under the title Dana’s New Mineralogy.
Danalite may be discovered during the localities which can be after in the USA, at Rockport and Gloucester, Essex County, Massachusetts; on Moat hill, Conway, Carroll County, New Hampshire; at Iron Mountain, Sierra County, New Mexico; and through the Black Hills, south of Jerome, Yavapai County, Arizona. From Needlepoint hill, McDame area, British Columbia, and on Walrus Island, James Bay, Quebec, Canada. In Sweden, from Yxsjö, Örebro. At Redruth, St. Just, Lanlivery, Falmouth, and Lanivet, Cornwall, England. In Russia, from Imalka, Transbaikal, and other localities which are less-well-defined. From the Kara mine, Tasmania, and on Mt. Francisco, Ribawa area, Western Australia. Within the Mihara mine, Hiroshima Prefecture, Japan.
| Category: | Sodalite – Feldspathoid |
| Chemical Formula: | Fe2+4Be3(SiO4)3S |
| Iron Beryllium Silicate Sulfide | |
| Molecular Weight: | 558.74 gm |
| Composition: | Beryllium | 4.84 % | Be | 13.43 % | BeO |
| Iron | 39.98 % | Fe | 51.43 % | FeO | |
| Silicon | 15.08 % | Si | 32.26 % | SiO2 | |
| Sulfur | 5.74 % | S | 5.74 % | S2- | |
| — | — % | S | -2.86 % | -O=S | |
| Oxygen | 34.36 % | O | |||
| 100.00 % | 100.00 % | = TOTAL OXIDE |
| Crystallography: | Isometric – Hextetrahedral |
| Crystal Habit: | As octahedral and dodecahedral crystals, to 10 cm; as irregular segregations. |
| Twinning: | None |
| Cleavage: | Poor/indistinct; poor on {111} |
| Fracture: | Irregular/uneven, sub-conchoidal |
| Tenacity: | Brittle |
| Mohs Hardness: | 5.5 – 6.0 |
| Density: | 3.28 – 3.26 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Not Radioactive |
| Color: | Yellow, pink, reddish brown, red; colorless to pink in thin section. |
| Transparency: | Translucent to semi-transparent |
| Luster: | Vitreous, Greasy |
| Refractive Index: | 1.747 – 1.771 Isotropic |
| Birefringence: | 0.000 – Isotropic minerals have no birefringence |
| Dispersion: | n/a |
| Pleochroism: | None |
