Henmilite
Henmilite may be a terribly rare mineral from the mineral category of “borates” (formerly carbonates, nitrates, and borates, see classification). It crystallizes among the anorthic crystal system with the formula Ca2CuB2(OH)12 is so with chemicals seen a Calcium, Copper, borate with extra hydroxide that is structural to the Mono borates belongs. The ninth edition of the Strunz’schen Mineral classification, that has been effective since 2001 and is used by the International Mineralogical Association (IMA), assigns the henmilite to the recently outlined category of “Borates” and there to the “Monoborate” department. This is often more divided when the development of the salt advanced and also there may be possible presence of extra anions, so the mineral in step with its composition within the segment “B(O,OH) 4 , with and while not extra anions; 1 (T), 1 (T) + OH, etc.”
Henmilite has (based about 12 oxygen atoms through the formula) the moderate administration Ca1.91 Cu0.99 B2.05 O12 H12.03 , which has been idealized in imitation of Ca2CuB2(OH)12 and has contents regarding 18, 85 B2O3 , 21.53% CuO, 30.36% CaO & amp; 28.26% H2O requires. Its Crystal structure is in the triclinic crystal system in the space group P 1 (space group number 2) along the lattice parameters a = 5.7617 Å ; b = 7.9774 Å; c = 5.6488 Å; Alpha = 109.611 °; Beta = 91.473 ° then Gamma = 83.686 ° or some method unit through soloist cell . In the henmilite, the boron is determined into isolated B(OH)4 groups then copper has a square-planar consistency by way of hydroxide ions. Calcium is surrounded by way of 8 hydroxide ions. The shape over the Henmilits consists regarding dimers about edge-sharing Ca(OH)2 – polyhedra with the aid of the square planar Cu(OH)4 groups are same in accordance with form a layer shape [01 parallel 1 ] is formed. The layers are B(OH)4 – tetrahedra linked after form a 3 – dimensional scaffold. The henmilite shape may additionally remain described of such a path so many dimers on Ca polyhedra are replaced by means of two B(OH)4 – Tetraeder are linked so that chains compare in imitation of [001] arise. These chains are attached in imitation of a 3-dimensional frame through square-planar Cu(OH)4 groups.
Henmilite is a very borate that is rare that comes from only one location in the planet; the Fuka mine, near Bicchu-cho, Takahashi, Okayama Prefecture, Chugoku Region, Honshu Island, Japan. The crystals are usually very small, to about 3 mm, and a very beautiful vivid bluish violet to color that is purple. Faceted gems are extremely unusual due to your small size of the crystals, the actual fact they truly are really delicate that they have been very soft (Mohs hardness of 1.5 – 2.0).
| Chemical Formula: | Ca2CuB2(OH)12 |
| Calcium Copper Hydroborate Hydroxide | |
| Molecular Weight: | 369.41 gm |
| Composition: | Calcium | 21.70 % | Ca | 30.36 % | CaO |
| Copper | 17.20 % | Cu | 21.53 % | CuO | |
| Boron | 5.85 % | B | 18.85 % | B2O3 | |
| Hydrogen | 3.27 % | H | 29.26 % | H2O | |
| Oxygen | 51.97 % | O | |||
| 100.00 % | 100.00 % | = TOTAL OXIDE |
| Crystallography: | Triclinic – Pinacoidal |
| Crystal Habit: | Minute triclinic pinacoidal crystals exhibit {100}, {010}, {101}, {102}, {110}, {011}, {142}, to 3 mm; massive. |
| Twinning: | None |
| Cleavage: | None |
| Fracture: | Fragile |
| Tenacity: | Fragile |
| Moh’s Hardness: | 1.5 – 2.0 |
| Density: | 2.51 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Not Radioactive |
| Color: | Bluish-Violet |
| Transparency: | Transparent |
| Luster: | Vitreous |
| Refractive Index: | 1.585 – 1.615 Biaxial ( – ) |
| Birefringence: | 0.0300 |
| Dispersion: | n/a |
| Pleochroism: | Strong; X = pale pink; Y = pale purple; Z = very pale blue |
