Helvine, also referred to as Helvite, is just a rare silicate that is manganese mineral that’s a person in the Helvine Group of minerals that also includes Danalite, Genthelvite and Tugtupite. Helvine can also be regarded as a Feldspathoid. Minerals with chemistries that are near to those associated with the feldspars that are alkali but are poor in silica (SiO2) content are called Feldspathoids. Helvine is termed from the Greek word ‘helvus’ for yellow or sun, in allusion to its color. The IMA formally respected title (2012 IMA list) is Helvine, not Helvite, although the synonym Helvite may become more common in collections and literature. Helvine are located in colors of yellow, pink, reddish brown or red, grayish yellowish and yellow-green. Faceted Helvine gems have become rare and often small but fairly large Quartz gems with Helvine crystal inclusions are occasionally available. One thing that Helvine and Quartz have as a common factor is that they’ve been both Pyroelectric. Pyroelectricity could be the ability of specific mineral crystals to generate a potential that is electric they are heated or cooled.
Helvine can be found at the localities that are following from Schwarzenberg and Breitenbrunn, Saxony, Germany. Exceptionally crystals that are large Yxsjö, Örebro, Sweden. At Luppikko, Karelia. In Russia, near Miass, Ilmen Mountains, Southern Ural Mountains. Through the Inyl’chek Mountains, Tien Shan, southeastern Kyrgyzstan. At Kara-Oba, Kazakhstan. From the Langesundsfjord, at Hørtekollen, and several other localities in Norway. In Finland, at Pitkäranta. In America, at Butte, Silver Bow County, Montana; from Amelia, Amelia County, Virginia; in the American Tunnel, Silverton, San Juan County, Colorado; on the fork that is eastern of Creek, Sawtooth Mountains, Boise County, Idaho; from the Clark vein, Rincon, San Diego County, California; at Iron Mountain, Sierra County, New Mexico. During the Navegadora Mine (Navegador Mine; Orozimbo Mine), Penha do Norte, Conselheiro Pena, Doce valley, Minas Gerais, Brazil. In China at Tongbei, Yunxiao County, Zhangzhou Prefecture, Fujian Province. In the Hongo mine, Iwate Prefecture; the Oashi mine, Tochigi Prefecture; the Yagisawa mine, Nagano Prefecture; and lots of other places in Japan. Within the Kara #1 Pit, Kara Mines, Hampshire district, Tasmania, Australia. A few localities that are additional known.
| Chemical Formula: | Mn2+4Be3(SiO4)3S |
| Manganese Beryllium Silicate Sulfide | |
| Molecular Weight: | 555.10 gm |
| Composition: | Manganese | 39.59 % | Mn | 51.12 % | MnO |
| Beryllium | 4.87 % | Be | 13.52 % | BeO | |
| Silicon | 15.18 % | Si | 32.47 % | SiO2 | |
| Sulfur | 5.78 % | S | 5.78 % | S2- | |
| — | — % | S | -2.88 % | -O=S | |
| Oxygen | 34.59 % | O | |||
| 100.00 % | 100.00 % | = TOTAL OXIDE |
| Crystallography: | Isometric – Hextetrahedral |
| Crystal Habit: | As tetrahedra, dodecahedra, and pseudo-octahedral crystals, up to 12 cm; as rounded grains. |
| Twinning: | None |
| Cleavage: | Distinct on {111} |
| Fracture: | Irregular/Uneven, Sub Conchoidal |
| Tenacity: | Brittle |
| Moh’s Hardness: | 6.0 – 6.5; VHN = 741 – 873 |
| Density: | 3.20 – 3.44 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Not Radioactive |
| Other: | Pyroelectric |
| Color: | Yellow, brown, red, gray-yellow, yellow-green |
| Transparency: | Translucent |
| Luster: | Vitreous to Resinous |
| Refractive Index: | 1.728 – 1.749 Isotropic |
| Birefringence: | 0.000 – Isotropic minerals have no birefringence |
| Dispersion: | n/a |
| Pleochroism: | None |
