Millerite
| Millerite | |
|---|---|
 |
|
| General and classification | |
| chemical formula | NiS |
|
Mineral class (and possibly department) |
Sulfides and sulfosalts |
|
System no. to Strunz and to Dana |
2.CC.20 ( 8th edition : II / C.21) 08/02/16/01 |
| Crystallographic Data | |
| Crystal system | trigonal |
| Crystal class ; symbol | ditrigonal-pyramidal; 3 m |
| Space group | R 3 m (No. 160) |
| Lattice parameters | a = 9.6071 Å ; c = 3.1434 Å |
| Formula units | Z = 9 |
| Twinning | under pressure along {0112} |
| Physical Properties | |
| Mohs hardness | 3.5 |
| Density (g / cm 3 ) | 5.374 |
| Cleavage | {1011} perfect, {0112} perfect |
| Break ; Tenacity | chopped up, brittle or uneven |
| colour | brass yellow, sometimes colored or gray |
| Line color | greenish black |
| transparency | opaque |
| shine | Metallic luster |
Millerite ( hair gravel , nickel gravel , yellow nickel gravel , hair pyrite , trichopyrite , chemical nickel (II) sulfide ) is a rather rarely occurring mineral from the mineral class of sulfides and sulfosalts . It crystallizes in the trigonal crystal system with the chemical composition NiS and usually develops thin, elongated crystals up to eight centimeters in length from brass yellow to bronze in color. These usually stand together as hair-like tufts.
Etymology and history
Millerite was first found in 1845 by Wilhelm Ritter von Haidinger in the type locality Jáchymov (Sankt Joachimsthal) in the Czech part of the Ore Mountains . It was named after the British mineralogist William Hallowes Miller , who first studied the mineral.
classification
In the Strunz system , millerite is classified as sulfides and sulfosalts. It is counted among the sulphides with a ratio of metal to sulfur, selenium or tellurium of 1: 1. In the eighth edition it formed a group with Lapieit , Mäkinenit , Mückeit and Zlatogorit . In the ninth edition , the alloys are also subdivided according to cations, where millerite with mäkinenite can be found in the class of metal sulfides with iron, cobalt or nickel.
In the systematics of minerals according to Dana it forms with mäkinenite a subgroup of sulfides - including selenides and tellurides - with the composition Am Bn Xp, with (m + n): p = 1: 1.
Crystal structure
Millerite crystallizes in the trigonal crystal system in the space group R3m with the lattice parameters a = 9.6071 Å and c = 3.1434 Å as well as nine formula units per unit cell . The structure corresponds to the nickel arsenide structure.
Education and Locations
Millerite usually forms in limestone or barite at low temperatures . Millerite can also be formed as a weathering product of other nickel minerals or in sediments. It is associated with gersdorffite , polydymite , nickeline , galena , sphalerite , pyrite , chalcopyrite , pyrrhotite , pentlandite , cubanite , calcite , dolomite , siderite , barite and anchorite .
A large number of sites (695 as of August 2009) are known for millerite. The sites include Müsen , Wissen , Ramsbeck , Lünen-Brambauer and Kamsdorf in Germany , Kotalahti in Finland , Kladno in the Czech Republic , Merthyr Tudful in Wales , Kambalda and Leinster in Australia , Bindura in Zimbabwe , Mabilikwe Hill in South Africa , Temagami , Thompson , Brompton Lake and Malartic in Canada , and Antwerp , Keokuk , St. Louis and Esterbrook Park in the United States .
use
Millerite is a nickel ore and is used as a raw material for the extraction of elemental nickel.
literature
- Millerite in: Anthony ua: Handbook of Mineralogy , 1990, 1, 101 ( pdf )
- Petr Korbel, Milan Novák: Encyclopedia of Minerals . Nebel Verlag GmbH, Eggolsheim 2002, ISBN 3-89555-076-0 , p. 34 .
Web links
Individual evidence
- ↑ a b c American Mineralogist Crystal Structure Database - Millerite (English, 1974)