Haüyne
Haüyne, also known as Haüynite, is really a known person in the Sodalite Group of minerals that includes Haüyne, Lazurite, Sodalite and Tugtupite. Haüyne is also thought to be described as a Feldspathoid. Minerals with chemistries that are near to those associated with feldspars that are alkalai but are poor in silica (SiO2) content, are known as Feldspathoids. Haüyne has one of the absolute most intense and beautiful colors that are blue the treasure globe. It is one of the major constituents of Lapis Lazuli and makes up the intense blue in Lapis. Faceted gems are rare and are often really small. The Eifel region of West Germany is the sole major source of gem quality material although Haüyne is found in several localities across the world.
Distribution: In Italy, in Lazio, at many localities within the Alban Hills, as at Ariccia, Marino, Sacrofano, and Campagnaro; on Monte Somma, and near Melfi, on Monte Vulture, Campania; in the Pitigliano quarry, near Grosseto, Tuscany. From Mendig, Mayen, and somewhere else in the Eifel region, Germany. In the USA, from Winnett, Petroleum County, Montana, and within the Edwards mine, St. Lawrence County, New York. In the Niangniang Shan complex, Nanjing, Jiangsu Province, China. On small island of Taiarupu, Tahiti. A few other localities that are small known.
| Category: | Tectosilicate, sodalite group |
| Chemical Formula: | (Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2 |
| Sodium Calcium Aluminum Silicate Sulfur Sulfate Chloride | |
| Molecular Weight: | 1,032.43 gm |
| Composition: | Sodium | 8.91 % | Na | 12.01 % | Na2O |
| Calcium | 7.76 % | Ca | 10.86 % | CaO | |
| Aluminum | 15.68 % | Al | 29.63 % | Al2O3 | |
| Silicon | 16.32 % | Si | 34.92 % | SiO2 | |
| Sulfur | 9.32 % | S | |||
| Chlorine | 1.72 % | Cl | 1.72 % | Cl | |
| – % | Cl | -0.39 % | -O=Cl2 | ||
| Oxygen | 40.29 % | O | |||
| 100.00 % | 96.50 % | = TOTAL OXIDE |
| Crystallography: | Isometric – Hextetrahedral |
| Crystal Habit: | Crystals are dodecahedra or pseudo-octahedra, to 3 cm; in rounded grains. |
| Twinning: | On {111}, common, rarely as penetration twins; also as polysynthetic or contact twins. |
| Cleavage: | Distinct on {110} |
| Fracture: | Irregular/Uneven to Conchoidal |
| Tenacity: | Brittle |
| Moh’s Hardness: | 5.0 – 6.0 |
| Density: | 2.40 – 2.50 (Eifel: 2.40) (g/cm3) |
| Luminescence: | May show reddish orange to purplish pink fluorescence under LW UV. |
| Radioactivity: | Not Radioactive |
| Color: | Bright blue to greenish blue; white or shades of black, gray, brown, green, yellow, red, may be patchy; colorless or pale blue in thin section. |
| Transparency: | Transparent to Translucent |
| Luster: | Vitreous to Greasy |
| Refractive Index: | 1.494 – 1.509 (Eifel: 1.502) Isotropic; weakly birefringent when included |
| Birefringence: | 0.000 (Isotropic) |
| Dispersion: | 0.008 |
| Pleochroism: | None |
