Triphylene
| Triphylene | |
|---|---|
 |
|
| General and classification | |
| chemical formula | LiFePO 4 |
|
Mineral class (and possibly department) |
Phosphates |
|
System no. to Strunz and to Dana |
8.AB.10 ( 8th edition : VII / A.02) 01/38/01/01 |
| Crystallographic Data | |
| Crystal system | orthorhombic |
| Crystal class ; symbol | orthorhombic-dipyramidal; 2 / m 2 / m 2 / m |
| Space group | Pnma |
| Lattice parameters | a = 10.332 Å ; b = 6.01 Å; c = 4.692 Å |
| Formula units | Z = 4 |
| Physical Properties | |
| Mohs hardness | 4 to 5 |
| Density (g / cm 3 ) | 3.5 to 3.6 |
| Cleavage | {001} perfect, {110} good, {100} very good |
| Break ; Tenacity | irregular |
| colour | greenish gray, speckled blue, brown |
| Line color | gray-white |
| transparency | translucent |
| shine | glassy to resinous |
| Crystal optics | |
| Refractive indices |
n α = 1.689 to 1.694 n β = 1.689 to 1.695 n γ = 1.695 to 1.702 |
| Axis angle | 2V = 0 to 55 ° |
Triphyline is a rather rarely occurring mineral from the mineral class of " phosphates , arsenates and vanadates ". It crystallizes in the orthorhombic crystal system with the chemical composition LiFePO 4 and rarely forms prismatic crystals , more often it is found hypidiomorphic in the rock. The mineral is blue to green-gray in color, aged brown to black.
Etymology and history
The mineral was first found and examined in 1834 by the German mineralogist Johann Nepomuk von Fuchs in a quartz quarry at Hennenkobel near Rabenstein in the Bavarian Forest . The name is derived from the Greek tri (three) and phulon (child, family), as the mineral contains three different cations ( iron , lithium , manganese ).
classification
In the old systematics of minerals according to Strunz (8th edition) , triphyline belongs to the division of "anhydrous phosphates without foreign anions ". Since the new systematics of minerals according to Strunz (9th edition) , however, this division has been more precisely divided according to the size of the cations . The mineral can now be found in the sub-section “anhydrous phosphates without foreign anions with medium-sized cations” and forms a separate group together with ferrisicklerite , heterosite , lithiophilite , natrophilite , purpurite , sicklerite and simferite .
The systematics of minerals according to Dana also assigns triphylenes to the category of "anhydrous phosphates", but specifies the general chemical formula "A + B 2+ XO 4 ".
Crystal structure
Triphyline crystallizes in the orthorhombic crystal system in the space group Pnma , the lattice parameters a = 10.332 Å , b = 6.01 Å and c = 4.692 Å as well as four formula units per unit cell . The lithium is coordinated in a distorted manner by six oxygen atoms, and the iron atoms are also coordinated in an octahedral manner . In addition, the structure contains isolated phosphate tetrahedra.
properties
Triphylene is soluble in hydrochloric and sulfuric acid. In front of the soldering tube , it melts to form a dark gray, magnetic ball. The mineral ages when the divalent iron oxidizes to trivalent iron and the lithium escapes from the triphyline. Here forms heterosite .
Modifications and varieties
Triphylenes form a mineral series with lithiophilite , in which the iron is replaced by manganese. Most naturally occurring triphyline also contains manganese. The mineral is isotypic with olivine .
Education and Locations
Triphylite is mainly used in granite - pegmatites ago. It is the most common phosphate mineral there. The mineral is associated with ferrisicklerite , heterosite , alluaudite and other iron-manganese oxides and phosphates as well as ore minerals such as spodumene , amblygonite , cassiterite and tantalite (Mn) .
In addition to the type locality, a number of other sites are known (February 2010: 232 sites). The more important ones include Hagendorf in Bavaria ( Germany ), Tammela in Finland , Skellefteå and Norrö in Sweden , Chanteloube and Huréaux in France , Bory in the Czech Republic , Governador Valadares in Brazil , Point de Bois in Canada, and Newport , Grafton , Newry , Keystone and Custer in the United States .
use
The triphylene found in Hagendorf, whose deposits amounted to around 1800 to 2000 tons, was smelted for the production of lithium.
See also
Individual evidence
- ^ A b V. A. Streltsov, EL Belokoneva, VG Tsirelson, NK Hansen: Multipole analysis of the electron density in triphylite, LiFePO4, using X-ray diffraction data . In: Acta Cryst. 1993, B49, pp. 147-153, doi : 10.1107 / S0108768192004701 .
- ↑ a b Mindat - Triphylite (English)
- ↑ a b Joh. Nep. Fuchs: About a new mineral (triphyline). In: Journal for Practical Chemistry. 1834, 3, pp. 98-104, doi : 10.1002 / prac.18340030120 .
- ↑ a b Joh. Nep. Fuchs: Mixed Notes, 3. Triphyline. In: Journal for Practical Chemistry. 1835, 5, p. 319, doi : 10.1002 / prac.18350050138 .
- ↑ Triphyline in: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( PDF ).
- ↑ Webmineral - New Dana Classification of Anhydrous Phosphates, etc.
- ^ VA Streltsov, EL Belokoneva, VG Tsirelson, NK Hansen: Multipole analysis of the electron density in triphylite, LiFePO4, using X-ray diffraction data . In: Acta Cryst. 1993, B49, pp. 147-153, doi : 10.1107 / S0108768192004701 .
- ↑ a b c Entry on triphyline. In: Römpp Online . Georg Thieme Verlag, accessed on January 2, 2015.
- ↑ Mindat - Lithiophilite-Triphylite Series (English)
