Hedenbergite
| Hedenbergite | |
|---|---|
 |
|
| General and classification | |
| chemical formula |
|
|
Mineral class (and possibly department) |
Silicates and germanates - chain and band silicates (inosilicates) |
|
System no. to Strunz and to Dana |
9.DA.15 ( 8th edition : VIII / F.01) 65.01.03a.02 |
| Similar minerals | Diopside , Augit |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | monoclinic prismatic; 2 / m |
| Space group | C 2 / c (No. 15) |
| Lattice parameters |
a = 9.84 Å ; b = 9.02 Å; c = 5.24 Å β = 104.8 ° |
| Formula units | Z = 4 |
| Twinning | polysynthetic twins according to {100} and {010} |
| Physical Properties | |
| Mohs hardness | 5.5 to 6.5 |
| Density (g / cm 3 ) | 3.56 to 3.65 |
| Cleavage | good after {110}; (110) or (110) ~ 87 ° |
| Break ; Tenacity | uneven to scalloped |
| colour | dark green, brown green, brown to black |
| Line color | white, gray |
| transparency | translucent to opaque |
| shine | Glass gloss, matt |
| Crystal optics | |
| Refractive indices |
n α = 1.699 to 1.739 n β = 1.705 to 1.745 n γ = 1.728 to 1.757 |
| Birefringence | δ = 0.029 |
| Axis angle | 2V = measured: 58 ° to 63 °; calculated: 56 ° to 72 ° |
| Pleochroism | weak: x = light green to blue-green; y = green to blue-green; z = green to yellow-green |
| Other properties | |
| Chemical behavior | Slightly soluble in hot hydrochloric acid |
| Special features | melts into black magnetic glass in front of the soldering tube |
Hedenbergite is a frequently occurring mineral from the mineral class of " silicates and germanates " with the idealized chemical composition CaFe 2+ [Si 2 O 6 ] and is therefore chemically a calcium - iron- silicate. Structurally, hedenbergite is one of the chain and band silicates (inosilicates).
Hedenbergite crystallizes in the monoclinic crystal system and develops mostly short prismatic, columnar to needle-like crystals up to about 5 cm in size in radial or large-stemmed mineral aggregates , but also occurs in the form of granular, leafy or coarse masses. of dark green, brown-green, brown or black color with white to gray stroke color .
Hedenbergit makes a perfect mixed batch with diopside and Johannsenite .
Etymology and history
Hedenbergite was first found in 1819 at Tunaberg near Nyköping in Sweden and described by Jöns Jakob Berzelius , who named the mineral after MA Ludwig Hedenberg , a Swedish chemist and employee of Berzelius.
classification
In the structural classification of the International Mineralogical Association (IMA) Hedenbergit belongs together with pyroxene , Burnettit , Davisit , diopside , Essenit , Grossmanit , Johannsenite , Kushiroit , Petedunnit and Tissintit to Kalziumpyroxenen (Ca pyroxene) in pyroxene .
In the meanwhile outdated, but still in use 8th edition of the mineral classification according to Strunz , the hedenbergite belonged to the department of " chain and band silicates (inosilicates) ", where together with aegirine , augite, diopside, essenite, jadeite , jervisite , johannsenite, kanoite , clino , Klinoferrosilit , Kosmochlor , Namansilit , Natalyit , omphacite , Petedunnit, pigeonite and spodumene the "pyroxene, clinopyroxene subgroup" with the system no. VIII / F.01 within the pyroxene group .
The 9th edition of Strunz's mineral systematics, which has been in force since 2001 and is used by the International Mineralogical Association (IMA), also classifies hedenbergite in the category of "chain and band silicates (inosilicates)". However, this department is further subdivided according to the type of chain formation, so that the mineral is classified in the subdivision “Chain and band silicates with 2-periodic single chains Si2O6; Pyroxene family "can be found, where together with Augite, Esseneit, Hedenbergite, Johannsenite and Petedunnit the" Ca-Klinopyroxene, diopside group "with the system no. 9.DA.15 forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the hedenbergite to the class of "silicates and germanates" and there in the department of "chain silicate minerals". Here it is together with Diopside, Augite, Johannsenite, Petedunnit, Esseneit and Davisite in the group of " C 2 / c Klinopyroxene (Ca-Klinopyroxene)" with the system no. 65.01.03a can be found in the subsection " Chain Silicates: Simple unbranched chains, W = 1 with chains P = 2 ".
Education and Locations
Hedenberg forms in metamorphic , calcium-rich rocks such as iron-bearing skarns and pyroxene - gneisses . But he can also magmatic in alkaline granites and syenites or in xenoliths of Kimberlith form. Accompanying mineral in iron formations is among other things the grunerite , in granites and syenites it is mainly arfvedsonite , fayalite and quartz .
So far (as of 2010) Hedenbergite has been found at around 450 sites worldwide, including in Afghanistan , Egypt , Algeria , Antarctica , Argentina , Ethiopia , Australia , Brazil , Bulgaria , Chile , China , Germany , Eritrea , France , Greece , Greenland , Guatemala , Honduras , Indonesia , Israel , Italy , Japan , Cameroon , Canada , Kenya , Colombia , North and South Korea , Kosovo , Madagascar , Morocco , Mexico , Mongolia , Namibia , Nepal , New Zealand , Nigeria , Norway , Oman , Austria , Pakistan , Peru , Poland , Portugal , Romania , Russia , Sweden , Switzerland , Spain , St. Lucia , Slovakia , South Africa , Tajikistan , Czech Republic , Turkey , Ukraine , Hungary , Uzbekistan , in the United Kingdom (Great Britain), in the United States (USA), Vietnam and Western Sahara .
Crystal structure
Hedenbergite crystallizes monoclinically in the space group C 2 / c with the lattice parameters a = 9.845 Å ; b = 9.024 Å; c = 5.245 Å and β = 104.74 ° as well as four formula units per unit cell .
See also
literature
- Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 718 (first edition: 1891).
- Martin Okrusch, Siegfried Matthes: Mineralogy. An introduction to special mineralogy, petrology and geology . 7th, completely revised and updated edition. Springer, Berlin [a. a.] 2005, ISBN 3-540-23812-3 , pp. 94 .
- Petr Korbel, Milan Novák: Mineral Encyclopedia (= Villager Nature ). Nebel Verlag, Eggolsheim 2002, ISBN 978-3-89555-076-8 , p. 233 .
Web links
- Mineral Atlas: Hedenbergite (Wiki)
- RRUFF Database-of-Raman-spectroscopy - Hedenbergite (English)
- American Mineralogist Crystal Structure Database - Hedenbergite (English)
Individual evidence
- ↑ a b Hans Jürgen Rösler : Textbook of Mineralogy . 4th revised and expanded edition. German publishing house for basic industry (VEB), Leipzig 1987, ISBN 3-342-00288-3 , p. 524 .
- ↑ a b IMA / CNMNC List of Mineral Names; November 2017 (PDF 1.67 MB)
- ↑ a b c d Hugo Strunz , Ernest H. Nickel : Strunz Mineralogical Tables. Chemical-structural Mineral Classification System . 9th edition. E. Schweizerbart'sche Verlagbuchhandlung (Nägele and Obermiller), Stuttgart 2001, ISBN 3-510-65188-X , p. 620 .
- ↑ Webmineral - Hedenbergite (English)
- ↑ a b c d Hedenbergite . In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America . 2001 ( handbookofmineralogy.org [PDF; 77 kB ; accessed on March 4, 2018]).
- ↑ a b c d e Mindat - Hedenbergite (English)
- ↑ Subcommite on Pyroxenes, CNMMN; Nobuo Morimoto: Nomenclature of Pyroxenes . In: The Canadian Mineralogist . tape 27 , 1989, pp. 143–156 ( mineralogicalassociation.ca [PDF; 1.6 MB ; accessed on November 11, 2018]).
- ↑ Find location list for Hedenbergite at the Mineralienatlas and at Mindat