Afghanite
Afghanite is is a rare mineral that is feldspathoid of Cancrinite Group of minerals and it is present in merely a few places worldwide. It really is often found connected with Lazurite and Sodalite. Crystals are blue to dark blue and often averagely to heavily included. Gems are typically included and small but beautiful shades of saturated blue. Afghanite ended up being discovered in 1968 in the Lapis-lazuli Mine, Sar-e-Sang, Badakhshan Province, Afghanistan and takes its name from that country.
Locations for Afghanite: at Sar-e-Sang, Badakhshan Province, Afghanistan. In Russia, in the Malaya Bystraya and Tultuy deposits being lazurite near Lake Baikal, as well as in other unspecified deposits in eastern Siberia. From Lyadzhuar-Darinsk, Pamir Mountains, Tajikistan. In Italy, at the Pitigliano quarry, near Grosseto, Tuscany; on Monte Somma, Campania; from Vetralla and Bassano, Latium. Within the Edwards mine, Edwards, St. Lawrence County, New York, USA. At Lake Harbour, Bafin Island, Newfoundland, Canada.
| Chemical Formula: | (Na,Ca,K)8(Si,Al)12O24(SO4,Cl,CO3)3 · H2O |
| Hydrated Sodium Calcium Potassium Aluminum Silicate Carbonate | |
| Molecular Weight: | 1,200.45 gm |
| Composition: | Potassium | 2.28 % | K | 2.75 % | K2O |
| Sodium | 9.19 % | Na | 12.39 % | Na2O | |
| Calcium | 11.69 % | Ca | 16.35 % | CaO | |
| Aluminum | 13.26 % | Al | 25.06 % | Al2O3 | |
| Silicon | 14.27 % | Si | 30.53 % | SiO2 | |
| Hydrogen | 0.08 % | H | 0.75 % | H2O | |
| Carbon | 0.10 % | C | 0.37 % | CO2 | |
| Sulfur | 3.39 % | S | 8.47 % | SO3 | |
| Chlorine | 4.58 % | Cl | 4.58 % | Cl | |
| — % | Cl | —1.03 % | —O=Cl2 | ||
| Oxygen | 41.16 % | O | |||
| 100.00 % | 100.00 % | = TOTAL OXIDE | |||
| Crystallography: | Hexagonal |
| Crystal Habit: | As stout to slender, thin tabular laths and as rounded grains or as massive – uniformly indistinguishable crystals forming large masses. |
| Twinning: | None |
| Cleavage: | Perfect on [1010] |
| Fracture: | Conchoidal |
| Tenacity: | Brittle |
| Moh’s Hardness: | 5.5 – 6.0 |
| Density: | 2.55 – 2.65 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Barely Detectable; GRapi = 32.54 (Gamma Ray American Petroleum Institute Units) |
| Color: | Light Blue to Dark Blue, Colorless |
| Transparency: | Transparent |
| Luster: | Vitreous |
| Refractive Index: | 1.523 – 1.529 Uniaxial ( + ) |
| Birefringence: | 0.006 |
| Dispersion: | n/a |
| Pleochroism: | None |
