Babingtonite
Babingtonite is just a calcium iron manganese mineral that is inosilicate is unusual in that iron(+3) completely replaces the aluminum so typical of silicate minerals. Theoretically speaking, Babingtonite contains both divalent (+2) and trivalent (+3) iron ions where aluminum ions would normally take a mineral that is a silicate. This causes Babingtonite to have a very magnetism that is poor. It is typically black colored but is often a very green that is dark. It really is typically opaque but may also be translucent (in slim crystals or slivers). Babingtonite often does occur with Zeolite group minerals in cavities in volcanic stones. In addition is the actual only real mineral that is black with the typical white or pale-colored Zeolites. This will make a contrast that is nice causes it to be obvious the ordinarily small Babingtonite crystals among the other minerals in a zeolitic pocket.
Babingtonite was first described in 1824 from samples from the Arendal Iron Mines, Arendal, Aust-Agder, Norway (the kind locality) and had been called after Dr. William Babington (May 21, 1756 - April 29, 1833), physician and mineralogist, curator of this John Stuart, 3rd Earl of Bute mineral collection until 1792, founding member and President (from 1822 to 1824) of the Geological Society of London and author of noted systematic books on mineralogy (1796 - 1799). Babingtonite could be the mineral that is official of Commonwealth of Massachusetts.
Understood from the quantity of localities, many minors; a few of the localities providing crystals that are good: in Norway, during the Branstad mine, Oyestad, near Arendal. From Gronsjöberg, Dalarna, Sweden. In Germany, at Herbornseelbach, Hesse. From Baveno, Piedmont, Italy. In the Kandivali quarry, near Bombay, Maharashtra, India. At Mitani, Kochi Prefecture, Japan. From Norilsk, western Siberia, Russia. Within the United States Of America, in Massachusetts, exemplary crystals from Lane's Quarry, Westfield, Hampden County; into the Cheapside and Deerfield quarries, East Deerfield, Franklin County; additionally at Winchester Highlands, Uxbridge, Norfolk County. At Paterson, Passaic County, and Mine Hill, Morris County, New Jersey; from the Goose Creek quarry, Leesburg, Loudoun County, Virginia; and also at Lenoir, Caldwell County, North Carolina.
Chemical Formula: | Ca2(Fe2+;Mn)Fe3+Si5O14(OH) |
Calcium Iron Manganese Silicate Hydroxide | |
Molecular Weight: | 573.05 gm |
Composition: | Calcium | 13.99 % | Ca | 19.57 % | CaO |
Manganese | 2.40 % | Mn | 3.09 % | MnO | |
Iron | 17.05 % | Fe | 21.94 % | FeO | |
Silicon | 24.51 % | Si | 52.43 % | SiO2 | |
Hydrogen | 0.18 % | H | 1.57 % | H2O | |
Oxygen | 41.88 % | O | |||
100.00 % | 98.60 % | = TOTAL OXIDE |
Cleavage: | Perfect on {001}, good on {010} and {100}. |
Fracture: | Irregular/Uneven to Subconchoidal |
Tenacity: | Brittle |
Moh's Hardness: | 5.5 - 6.0 |
Density: | 3.34 - 3.37 (g/cm3) |
Luminescence: | None |
Radioactivity: | Not Radioactive |
Other: | Weakly Magnetic |
Crystallography: | Triclinic - Pinacoidal |
Crystal Habit: | Stubby, prismatic, striated crystals, to 3 cm; also platy and as subparallel aggregates. |
Twinning: | None |
Cleavage: | Perfect on {001}, good on {010} and {100}. |
Fracture: | Irregular/Uneven to Subconchoidal |
Tenacity: | Brittle |
Moh's Hardness: | 5.5 - 6.0 |
Density: | 3.34 - 3.37 (g/cm3) |
Luminescence: | None |
Radioactivity: | Not Radioactive |
Other: | Weakly Magnetic |
Color: | Almost always black; black to dark greenish black |
Transparency: | Opaque to faintly translucent in thin crystals or splinters |
Luster: | Vitreous |
Refractive Index: | 1.700 - 1.725 Biaxial ( - ) |
Birefringence: | 0.025 |
Dispersion: | Strong; r > v |
Pleochroism: | X = deep green; Y = lilac-brown; Z = pale to deep brown. |