Katophorite
The Katophorite minerals are sodium-calcium Amphiboles with varying amounts of magnesium (Mg), iron (Fe) and alumiunum (Al). The varieties of Katophorite are named according for their chemical composition. Examples are: Ferri-Katophorite is named for its iron that is ferric dominance Ferro-Katophorite is known as for its ferrous iron dominance; Magnesio-Katophorite is known as for its magnesium dominance, and so on. At this time there are nine varieties with Katophorite as various element name modifiers for their base name.
The Kataphorite Group species magnesium that is containingMg) and with ferric iron (Fe3+) greater than aluminum (Al) within the C place was known as Magnesio-Katophorite in the 1978 and 1997 IMA amphibole nomenclature. Nevertheless, the Katophorite Group minerals were redefined in the 2012 IMA amphibole nomenclature. The 2012 modification renamed the Mg, Fe3+ and (OH) member that is principal of group Ferri-Katophorite.
The mineral Katophorite ended up being first described by W.C. Brøgger (1894) as an mineral that is amphibole he found at three localities in the Permian Oslo Region, Norway. The minerals initially designated by Brøgger (1894) as “Katophorite” are, based on the Amphibole that is new nomenclature classified as Ferro-Katophorite. Katophorite, without any element modifiers, is the title given to an Amphibole occurance found in 2013 at the Hpakant-Tawmaw Jade Tract, Hpakant Township, Mohnyin District, Kachin State, northern Myanmar (Burma). Katophorite is known as from the Greek term
κατώφορος (kataphora) meaning holding down, in allusion to its volcanic origin.
Katophorite is normally black, dark greenish bluish or black black with vitreous luster and frequently opaque but may also be clear to translucent in thin slivers. Black Katophorite Is frequently discovered associated with greenish arfvedsonite that is black white Feldspar, and red Eudialyte at the Kipawa alkaline complex in Canada (see treasure pictured above). This will make for a very unusual and gem that is attractive.
Circulation: may take place in the Oslo (Christiania) district, Norway, from where it had been initially described. On the Rallier-du-Baty Peninsula, Kerguelen Island, into the Indian that is south Ocean. Within the Kipawa alkaline complex, Les Lacs-du-Témiscamingue, Témiscamingue RCM, Abitibi-Témiscamingue, Québec, Canada. At the Hpakant-Tawmaw Jade Tract, Hpakant Township, Mohnyin District, Kachin State, northern Myanmar (Burma).
| Chemical Formula: | Na[NaCa][(Fe2+,Mg)4Al](Si7Al)O22(OH)2 |
| Sodium Calcium Iron Magnesium Aluminum Silicate Hydroxide | |
| Emperical Chemical Formula: | Na1.2K0.3Ca1.3Fe2+3.25Mg1.5Ti0.2Mn2+0.2Al0.7Si7.3O22(OH)22 |
| Molecular Weight: | 939.86 gm |
| Composition: | Potassium | 1.25 % | K | 1.50 % | K2O |
| Sodium | 2.94 % | Na | 3.96 % | Na2O | |
| Calcium | 5.54 % | Ca | 7.76 % | CaO | |
| Magnesium | 3.88 % | Mg | 6.43 % | MgO | |
| Titanium | 1.02 % | Ti | 1.70 % | TiO2 | |
| Manganese | 1.17 % | Mn | 1.51 % | MnO | |
| Aluminum | 2.01 % | Al | 3.80 % | Al2O3 | |
| Iron | 19.31 % | Fe | 24.84 % | FeO | |
| Silicon | 21.81 % | Si | 46.67 % | SiO2 | |
| Hydrogen | 0.21 % | H | 1.92 % | H2O | |
| Oxygen | 40.86 % | O | |||
| 100.00 % | 100.09 % | = TOTAL OXIDE | |||
| Crystallography: | Monoclinic – Prismatic |
| Crystal Habit: | Prismatic, granular, also as fibrous aggregates or dendrites and skeletal crystals. Commonly rimming other minerals. |
| Twinning: | || {100} |
| Cleavage: | Perfect on {110}, intersecting at ~56° and ~124°; parting on {010} |
| Fracture: | Conchoidal |
| Tenacity: | Brittle |
| Moh’s Hardness: | 5.0 – 6.0 |
| Density: | 3.2 – 3.5 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Not Radioactive |
| Color: | Black, dark green-black, bluish black; reddish yellow, bluish green in thin section |
| Transparency: | Transparent to translucent, opaque |
| Luster: | Vitreous |
| Refractive Index: | 1.640 – 1.692 Biaxial ( – ) |
| Birefringence: | 0.020 |
| Dispersion: | Strong, r < v |
| Pleochroism: | Strong; reddish yellow, reddish brown, and dark green to black |
| Anisotropism: | n/a |
