Boracite
Boracite is one of many rarest of collector’s gems. The sole crystals that are facetable through the Stassfurt and Hanover districts of Germany. Boracite crystals are really small and gems that are cut usually very pale blue to green or colorless. Boracite is the magnesium analog of Chambersite. Boracite is a mineral that is evaporite isn’t surprisingly found with other evaporite minerals like Anhydrite, Gypsum, and Halite. Boracite crystals are often embedded in these other evaporite minerals.
Boracite is one of the rare minerals that display both the piezoelectric impact and the effect that is pyroelectric. Piezoelectricity is the capability of some mineral crystals to generate a voltage in response to applied stress that is mechanical as an external pressure or stress. Piezoelectricity ended up being found in 1880 by French physicists, brothers Jacques and Pierre Curie. Pyroelectricity could be the ability of certain mineral crystals to produce a charge that is electrical they are heated or cooled. The reference that is first the pyroelectric effect is in writings by Theophrastus in 314 BC, who noted that Tourmaline becomes charged when heated. Sir David Brewster offered the impact the name this has in 1824 today. Both William Thomson in 1878 and Voight in 1897 assisted to create a theory for the processes behind pyroelectricity. Boracite can also be a water mineral that is soluble.
Boracite distribution: in Germany, from Lüneburg, 40 km south-southeast of Hamburg, Lower Saxony; in Saxony-Anhalt, into the Stassfurt-Westeregeln-Bernburg region, at the Douglashall, Berlepsch, Solvayhall, Wilhelmshall along with other mines; in Thuringia, from Bischofferode, within the Glückauf mine, Sondershausen, and elsewhere. In France, at Lunéville, Meurthe-et-Moselle. Within the Boulby potash mine, north-west of Whitby, Yorkshire, England. In the salt that is chelkar, Ak-sai Valley, Uralsk district, Kazakhstan. Large crystals from Alto Chapare, Cochabamba, Bolivia. Into the USA, in the salt that is Choctaw, Iberville Parish, Louisiana, and the Louann Salt Formation, Clarke County, Alabama. From the Penobsquis and Salt Springs evaporite deposits, near Sussex, brand new Brunswick, Canada.
| Category: | Tektoborates |
| Chemical Formula: | Mg3B7O13Cl |
| Magnesium Borate Chloride | |
| Molecular Weight: | 392.03 gm |
| Composition: | Magnesium | 18.60 % | Mg | 30.84 % | MgO |
| Boron | 19.30 % | B | 62.15 % | B2O3 | |
| Chlorine | 9.04 % | Cl | 9.04 % | Cl | |
| – | – % | Cl | -2.04 % | -O=Cl2 | |
| Oxygen | 53.06 % | O | |||
| 100.00 % | 100.00 % | = TOTAL OXIDE |
| Crystallography: | Orthorhombic – Pyramidal |
| Crystal Habit: | Euhedral crystals, to 2.5 cm, (referred to pseudo tetrahedral morphology) and a dozen other modifying forms; spherulitic, plumose to fibrous, fine granular aggregates. |
| Twinning: | Rarely as penetration twins |
| Cleavage: | None observed |
| Fracture: | Conchoidal to Irregular/Uneven |
| Tenacity: | Brittle |
| Moh’s Hardness: | 7.0 – 7.5 |
| Density: | 2.91 – 3.10 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Not Radioactive |
| Other: | Strongly piezoelectric and pyroelectric. Very slowly decomposed by water. Slowly but completely soluble in HCl. At 265° the crystal system reverts to a high-temperature phase and the material becomes isotropic. Forms pseudomorphs after quartz (Douglashall). |
| Color: | Pale green, greenish blue, blue, colorless, grey, white; dark green (ferroan) |
| Transparency: | Transparent, Translucent |
| Luster: | Adamantine to Vitreous |
| Refractive Index: | 1.658 – 1.673 Biaxial ( + ) |
| Birefringence: | 0.010 – 0.011 |
| Dispersion: | 0.024 (weak) |
| Pleochroism: | None |
