Chalcanthite
| Chalcanthite | |
|---|---|
 |
|
| General and classification | |
| other names |
|
| chemical formula | Cu [SO 4 ] • 5H 2 O |
|
Mineral class (and possibly department) |
Sulfates (and relatives) |
|
System no. to Strunz and to Dana |
7.CB.20 ( 8th edition : VI / C.04) 06/29/07/01 |
| Similar minerals | Jokokuit , pentahydrite , siderotile |
| Crystallographic Data | |
| Crystal system | triclinic |
| Crystal class ; symbol | triclinic pinacoidal; 1 |
| Room group (no.) | P 1 (No. 2) |
| Lattice parameters |
a = 6.12 Å ; b = 10.72 Å; c = 5.96 Å, α = 82.4 °; β = 107.3 °; γ = 102.6 ° |
| Formula units | Z = 2 |
| Twinning | rarely cross twins |
| Physical Properties | |
| Mohs hardness | 2.5 |
| Density (g / cm 3 ) | measured on the synthetic crystal: 2.286; calculated: 2.282 |
| Cleavage | indistinct |
| Break ; Tenacity | shell-like |
| colour | light to dark blue, rarely green or green-blue |
| Line color | White |
| transparency | transparent to translucent |
| shine | Glass gloss to resin gloss |
| Crystal optics | |
| Refractive indices |
n α = 1.514 n β = 1.537 n γ = 1.543 |
| Birefringence | δ = 0.029 |
| Optical character | biaxial negative |
| Axis angle | 2V = measured: 56 °; calculated: 56 ° |
| Other properties | |
| Special features | soluble in water, dehydrated in air |
Chalcanthite , also known in chemistry as copper sulfate (more precisely copper sulfate pentahydrate) and out of date generally known as copper vitriol , is a rather seldom occurring mineral from the mineral class of " sulfates (and relatives )". It crystallizes in the triclinic crystal system with the chemical composition Cu [SO 4 ] · 5 H 2 O and develops mostly crusty coatings or fibrous or granular aggregates , rarely also small, prismatic to tabular crystals in light to dark blue color. Green to green-blue crystals are also very rarely found.
Etymology and history
The name chalcanthite (cf. Latin calcantum ) is a combination of the Greek words χαλκός chalkós for " copper " and ἄνθος ánthos for "blossom".
The mineral was first scientifically described in 1853 by Franz von Kobell .
classification
In the meanwhile outdated, but still in use 8th edition of the mineral classification according to Strunz , the chalcanthite belonged to the mineral class of "sulfates, chromates, molybdates and tungstates" and there to the department of "hydrous sulfates without foreign anions ", where it was named after the "chalcanthite" -Group "with the system no. VI / C.04 and the other members Jôkokuit , Pentahydrite and Siderotil .
The 9th edition of Strunz's mineral systematics , valid since 2001 and used by the International Mineralogical Association (IMA), assigns chalcanthite to the extended class of "sulfates (including selenates, tellurates, chromates, molybdates and tungstates)" and there into the department the "sulfates (selenates etc.) without additional anions, with H 2 O". However, this is further subdivided according to the size of the cations involved , so that the mineral can be found according to its composition in the sub-section “With only medium-sized cations”, where together with jokokuit, pentahydrite, sanderite and siderotile the “pentahydrite group” with the system -No. 7.CB.20 forms.
The systematics of minerals according to Dana also assigns chalcanthite to the class of "sulphates, chromates and molybdates", but in the more finely subdivided division of "water-containing acids and sulphates". Here he is together with Siderotil, Pentahydrite and Jôkokuit in the "Chalcanthite group (Triklin: P 1 )" named after him with the system no. June 29, 2007 to be found in the subsection of " Water-containing acids and sulfates with AXO 4 • x (H 2 O) ".
properties
Chalcanthite becomes dehydrated in air. It should therefore be kept in the absence of air if possible so that the crystals do not disintegrate. Too much water, however, dissolves the chalcanthite crystals. However, dehydration in the early stages can be cured by brief, careful brushing under water. It is easier, if available, to place the steps in a saturated copper sulfate solution.
With a Mohs hardness of 2.5, chalcanthite is one of the soft minerals (can still be scratched with a fingernail). Its transparent to translucent crystals show a resin to glass sheen on the surface.
Crystal structure
Chalcanthite crystallizes triclinically in the space group P 1 (space group no. 2) with the lattice parameters a = 6.12 Å ; b = 10.72 Å; c = 5.96 Å; α = 82.4 °; β = 107.3 ° and γ = 102.6 ° as well as 2 formula units per unit cell . Copper is coordinated in octahedra of oxygen distorted by the Jahn-Teller effect , whereby these octahedra are linked to form chains by two tetrahedral sulfate ions . The remaining oxygen atoms come from water molecules that hold the chains together through hydrogen bonds .
Education and Locations
Chalcanthite is formed by the oxidation of copper sulphides , especially chalcopyrite , although it is only stable in arid climates . Very often it can be found in abandoned tunnels in the old man . Accompanying minerals include brochantite , epsomite , fibroferrite , gypsum , goslarite , melanterite , morenosite , pickeringite , retgersite and rhomboclase .
So far (as of 2011), chalcanthite has been found at around 760 sites worldwide. In addition to its type locality " Chuquicamata Mine" in the Chilean Región de Antofagasta , important sites include Bisbee in Arizona in the USA, where crystals up to four centimeters in size and stalactites up to one meter in size were found.
In Germany, chalcanthite was found in several areas of the Black Forest in Baden-Württemberg; in Franconia , Lower Bavaria and the Upper Palatinate in Bavaria; near Dillenburg , in the Odenwald and near Richelsdorf in Hesse; in the Harz region of Lower Saxony ; in many regions of the Eifel from North Rhine-Westphalia to Rhineland-Palatinate; the Niederbergisches Land , in the Ruhr area , the Sauerland and Siegerland in North Rhine-Westphalia; in the district of Mansfeld-Südharz in Saxony-Anhalt; in the Ore Mountains , Upper Lusatia and Vogtland in Saxony as well as near Bad Lobenstein , Gera and Saalfeld in Thuringia.
In Austria the mineral could be found in many regions of Carinthia and Salzburg as well as on the Hochlantsch and near Knittelfeld in Styria and in the Inntal in North Tyrol. In Switzerland, chalcanthite has so far been found near Obersaxen (Graubünden), Intschi ( Reuss Valley , Uri) as well as near Saint-Luc VS and Martigny (Valais).
Other locations are Afghanistan , Egypt , Argentina , Australia , Bolivia , Bulgaria , Chile , China , Democratic Republic of the Congo , Ecuador , El Salvador , France , Greece , Guatemala , Iran , Ireland , Italy , Japan , Canada , Kazakhstan , Colombia , Kosovo , Cuba , Luxembourg , Madagascar , Morocco , Mexico , Namibia , New Caledonia , New Zealand , North Korea , Norway , Peru , Philippines , Poland , Portugal , Romania , Russia , Sweden , Slovakia , Slovenia , Spain , South Africa , Romania, Czech Republic , Hungary , Turkey , several regions in the United Kingdom , many regions in the United States, and Cyprus .
Galitzenstein is an old name for both copper sulphate (copper vitriol) and zinc salts (zinc sulphate, zinc vitriol) from the ore-rich northern Spanish landscape of Galicia .
use
As a raw material
Chalcanthite is an important copper ore .
See also
literature
- Friedrich Klockmann ; Paul Ramdohr, Hugo Strunz (editor): Klockmann's textbook of mineralogy . 16th, revised and expanded edition. Enke , Stuttgart 1980, ISBN 3-432-82986-8 (first edition 1891).
- Petr Korbel, Milan Novák: Encyclopedia of Minerals . In: Dörfler Natur . Edition Dörfler im Nebel-Verlag, Eggolsheim , ISBN 978-3-89555-076-8 (Original title: The Complete Encyclopedia of Minerals. Descriptions of over 600 Minerals from Around the World by Petr Korbel and Milan Novak, by Chartwell Books, Edison NJ 1999 ISBN 0-7858-1520-1 . Translated by Werner Horwath, [2008]).
Web links
- Mineral Atlas: Chalcanthite (Wiki)
- Webmineral - Chalcanthite (English)
- MinDat - Chalcanthite (English)
Individual evidence
- ↑ a b c d e Hugo Strunz , Ernest H. Nickel: Strunz Mineralogical Tables . 9th edition. E. Schweizerbart'sche Verlagbuchhandlung (Nägele and Obermiller), Stuttgart 2001, ISBN 3-510-65188-X , p. 382 .
- ↑ Webmineral - Chalcanthite (English)
- ↑ a b c Chalcanthite at mindat.org (English)
- ↑ Robert Damme: The Stralsund vocabulary. Edition and investigation of a Middle Low German-Latin vocabulary manuscript from the 15th century. Cologne / Vienna 1989 (= Low German Studies. Volume 34), p. 212 ("Ghalliciensten: Kopperok, atramentum viride, calcantum, cuperosa, dragantum, vitriolum album, vitriolum romanum, zegi").
- ↑ LD Iskhakova, VK Trunov, TM Shchegoleva, VV Ilyukhin, AA Vedernikov: Crystal structure of chalcanthite CuSO 4 · 5H 2 O grown under microgravity . In: Soviet Physics - Crystallography . 1983, pp. 383-387.
- ↑ Mindat - Localities for Chalcanthite
- ^ Emil Ernst Ploß: A book of old colors. Technology of textile colors in the Middle Ages with an outlook on solid colors. 6th edition. Munich 1989, ISBN 978-3-89164-060-9 , pp. 86 and 180.