Rhodonite
| Rhodonite | |
|---|---|
 |
|
| General and classification | |
| other names |
Pajsbergite |
| chemical formula |
|
|
Mineral class (and possibly department) |
Silicates and Germanates |
|
System no. to Strunz and to Dana |
9.DK.05 ( 8th edition : VIII / D.13) 65.04.01.01 |
| Similar minerals | Bustamit |
| Crystallographic Data | |
| Crystal system | triclinic |
| Crystal class ; symbol | triclinic pinacoidal; 1 |
| Space group | P 1 (No. 2) |
| Lattice parameters |
a = 7.682 Å ; b = 11.818 Å; c = 6.707 Å, α = 92.355 °; β = 93.948 °; γ = 105.665 ° |
| Formula units | Z = 10 |
| Frequent crystal faces | {010}, {100}, {001}, {110}, {22 1 }, {2 2 1 } |
| Twinning | Slats // {010} |
| Physical Properties | |
| Mohs hardness | 5.5 to 6.5 |
| Density (g / cm 3 ) | measured: 3.57 to 3.76; calculated: 3.726 |
| Cleavage | completely according to {110} and {1 1 0}; good after {001} |
| Break ; Tenacity | shell-like to uneven |
| colour | pink to red, brownish red, gray-yellow |
| Line color | White |
| transparency | transparent to translucent |
| shine | Glass to mother-of-pearl gloss |
| Crystal optics | |
| Refractive indices |
n α = 1.711 to 1.738 n β = 1.714 to 1.741 n γ = 1.724 to 1.751 |
| Birefringence | δ = 0.013 |
| Optical character | biaxial positive |
| Axis angle | 2V = 58 ° to 73 ° (measured); 58 ° (calculated) |
| Pleochroism | weak: X = yellowish red Y = pinkish red Z = light yellowish red |
| Other properties | |
| Chemical behavior | slowly attacked by HCl; difficult to dye; weathered to manganese oxides |
The mineral rhodonite (also pajsbergite ) is a frequently occurring chain silicate from the mineral class of " silicates and germanates " with the idealized chemical composition Mn 2+ SiO 3 and thus, chemically speaking, a manganese silicate.
Rhodonite crystallizes in the triclinic crystal system and develops mostly granular to massive mineral aggregates of pink to red, brownish-red or gray-yellow color, which are often pervaded by black manganese oxide veins. Tabular to columnar crystals , often rounded at the corners, belong to the rare training variants .
Etymology and history
The name "Rhodonite" is derived from the ancient Greek language . The word occurs there in the Attic dialect as ῥόδον [rʰódon] or in the Aiolic dialect βρόδον [brʰódon] "rose (nduft)" and is already in Mycenaean Greek as [wo-do-we] / u̯rodóu̯en / "the rosy / rose-scented “Occupied. It can be found in Armenian as “vard” and in Latin as “rosa” and passed through Latin into the German word “ rose ”.
The mineral was first scientifically described in 1819 by Christoph Friedrich Jasche , who also named it after the Greek word for rose because of its color. The type locality is the Schävenholz manganese mine near Elbingerode (Harz) in the Elbingeröder complex in Saxony-Anhalt.
classification
Already in the outdated 8th edition of the mineral classification according to Strunz , the rhodonite belonged to the mineral class of "silicates and germanates" and there to the department of "chain silicates and band silicates (inosilicates)", where it was named after the "rhodonite series" with the system No. VIII / D.13 and the other members Babingtonit and Manganbabingtonit formed.
In the last revised and updated Lapis mineral directory by Stefan Weiß in 2018 , which, out of consideration for private collectors and institutional collections, is still based on this classic system of Karl Hugo Strunz , the mineral was given the system and mineral number. VIII / F.27-10 . In the “lapis system” this also corresponds to the “chain and band silicates” department, where rhodonite, together with babingtonite , ferrorhodonite , fowlerite , inesite , lithiomarsturite , manganeseabingtonite , marsurite , nambulite , soda lambulite , santaclaraite and scandiobabingtonite forms an unnamed group Members contain structures with five-chain [Si 5 O 15 ] 10- ∞ .
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and was updated by the International Mineralogical Association (IMA) until 2009, also classifies rhodonite in the "chain and band silicates" department. This is, however, further subdivided according to the structural chain, so that the mineral can be found in the sub-section "Chain and ribbon silicates with 5-periodic single chains, Si 5 O 15 ", where it is also found together with babingtonite, fowlerite (Q) , Lithiomarsturit, Manganbabingtonit, Marsturit, Nambulit, Natronambulit, and Scandiobabingtonit "Rhodonitgruppe" with the system no. 9.DK.05 forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , also assigns rhodonite to the class of "silicates and Germanates" and there in the department of "chain silicate minerals". Here, too, it is in the "Rhodonite group" with system no. 65.04.01 to be found in the sub-section " Chain Silicates : Simple unbranched chains, W = 1 with chains P = 5 ".
Chemism
The idealized (theoretical) composition of rhodonite (Mn 2+ SiO 3 ) consists of 41.93 wt% manganese (Mn), 21.44 wt% silicon (Si) and 36.63 wt% oxygen ( O). In the analysis of mineral samples, however, were different foreign admixtures such as, among others, iron, magnesium and calcium, the manganese in the formula represented can and found aluminum as a representative for the silicon.
Crystal structure
Rhodonite crystallizes triclinically in the space group P 1 (space group no. 2) with the lattice parameters a = 7.682 Å ; b = 11.818 Å; c = 6.707 Å; α = 92.355 °; β = 93.948 ° and γ = 105.665 ° as well as 10 formula units per unit cell .
Modifications and varieties
The compound is dimorphic and occurs in nature, in addition to the triclinic crystallizing rhodonite, also triclinic, but with different lattice parameters crystallizing pyrox mangite .
Two varieties of rhodonite are known so far :
- Fowlerit is a zinc-containing Rhodonit with a color cast towards brown or yellowish as including in Franklin / New Jersey were found.
- Hsihusunit is a magnesium-containing rhodonite of red-violet color.
Education and Locations
Rhodonite is mainly formed in metamorphic rocks rich in manganese , but can also be formed in ore veins by hydrothermal processes . Accompanying minerals include alleghanyite , calcite , franklinite , galaxite , galena , grunerite , magnetite , various manganese oxides , spessartine , tephroit and willemite .
As a frequently occurring mineral formation, rhodonite can be found at many sites, with around 1000 sites being documented so far (as of 2019). In addition to its type locality Schävenholz, the mineral was also found in Saxony-Anhalt in the Sengelbachtal near Biesenrode in the Mansfeld region. Other previously known localities in Germany include the Heinrich shaft at Gailbach in Bavaria, the marble - quarry Dr. Linck near Hochstädten (Bensheim) , as well as the Ferdinand mines near Nanzenbach and Bornberg near Seelbach (Herborn) in Hesse; in a gabbro quarry (also called bear quarry ) in the Radautal near Bad Harzburg in Lower Saxony, as well as at the Krufter furnace , in the In den Dellen opencast mine (also known as the Zieglowski mine ), in the area around Thelenberg and in the Wingertsberg opencast mine near Mendig in Rhineland-Palatinate.
Other world-famous sites are among others in Argentina ; in several New South Wales counties, Australia; Municipio Todos Santos in Bolivia; Bahia , Paraíba and Minas Gerais in Brazil; Bulgaria ; several regions of China ; Costa Rica ; Vaasa in Finland; Lorraine and Midi-Pyrénées in France; Greece ; England and Wales in Great Britain; India ; Indonesia ; in several regions of Italy ; Hokkaidō , Honshū , Kyūshū , Shikoku and on the Nansei Islands in Japan; Canada ; Kyrgyzstan ; Toliara in Madagascar; several regions of Mexico ; near Grootfontein in Namibia; Otago in New Zealand; North Korea ; Norway ; several regions of Peru ; on the Philippines island of Luzon ; at Castro Verde in Portugal; at several sites in each of the regions of Carinthia , Salzburg , Styria and Tyrol in Austria; Romania ; several regions of Russia ; Saudi Arabia ; several regions of Sweden ; in the Swiss cantons of Graubünden , Canton Uri and Valais ; Banská Bystrica and Košice in Slovakia; South Africa ; Andalusia and Catalonia in Spain ; Taiwan ; Bohemia in the Czech Republic; Turkey ; as well as in many regions of the United States .
Use as a gem stone
Rhodonit is exclusively for precious stones processed and is ground in the form of table stones , Cabochonen and beads for necklaces and other crafts items on sale. Transparent varieties are also given a facet cut.
Depending on the color nuance and quality in terms of purity and transparency, there is a risk of confusion with other minerals such as the pink, but mostly white striped rhodochrosite ; the also pink to red thulite , a manganese-containing variety of zoisite ; the chemically identical pyrox mangite ; the garnet minerals such as B. Spessartine and Hessonite ; the red spinel and tourmaline varieties .
Esoteric
In esotericism , rhodonite is considered a healing stone with an influence on the sacral and heart chakra and is said to have a pain-relieving and calming effect. Depending on the source, it is assigned to the zodiac sign Taurus or Cancer. However, there is no scientific evidence of its effectiveness.
See also
literature
- Petr Korbel, Milan Novák: Mineral Encyclopedia (= Villager Nature ). Edition Dörfler im Nebel-Verlag, Eggolsheim 2002, ISBN 978-3-89555-076-8 , p. 244 .
- Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 734 (first edition: 1891).
Web links
- Mineral Atlas: Rhodonite (Wiki)
- Rhodonite search results. In: rruff.info. Database of Raman spectroscopy, X-ray diffraction and chemistry of minerals (RRUFF), accessed on July 14, 2019 .
- American-Mineralogist-Crystal-Structure-Database - Rhodonite. In: rruff.geo.arizona.edu. Accessed July 14, 2019 .
Individual evidence
- ↑ a b Malcolm Back, William D. Birch, Michel Blondieau and others: The New IMA List of Minerals - A Work in Progress - Updated: May 2019. (PDF 1703 kB) In: cnmnc.main.jp. IMA / CNMNC, Marco Pasero, March 2019, accessed May 20, 2019 .
- ↑ a b c Stefan Weiss: The large Lapis mineral directory. All minerals from A - Z and their properties. Status 03/2018 . 7th, completely revised and supplemented edition. Weise, Munich 2018, ISBN 978-3-921656-83-9 .
- ^ 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. 647 (English).
- ↑ a b c d DR Peacor, N. Niizeki: The redetermination and refinement of the crystal structure of rhodonite, (Mn, Ca) SiO 3 . In: Journal of Crystallography . tape 119 , 1963, pp. 98–116 (English, rruff.info [PDF; 931 kB ; accessed on July 14, 2019] With a brief description in German).
- ^ David Barthelmy: Rhodonite Mineral Data. In: webmineral.com. Accessed July 14, 2019 .
- ↑ a b c Rhodonite . In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America . 2001 (English, handbookofmineralogy.org [PDF; 76 kB ; accessed on July 14, 2019]).
- ↑ a b c d e f g Rhodonite. In: mindat.org. Hudson Institute of Mineralogy, accessed July 14, 2019 .
- ↑ Ernest H. Nickel, Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF 1703 kB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed April 25, 2019 .
- ↑ Rhodonite. In: Mineralienatlas Lexikon. Stefan Schorn u. a., accessed on July 14, 2019 .
- ↑ Linda R. Pinckney, Charles W. Burnham: Effects of compositional variation on the crystal structures of pyroxmangite and rhodonite . In: American Mineralogist . tape 73 , 1988, pp. 798–808 ( rruff.info [PDF; 1.4 MB ; accessed on July 15, 2019]).
- ^ A b Karl Hugo Strunz , Christel Tennyson : Mineralogical tables . 8th edition. Academic publishing company Geest & Portig KG, Leipzig 1982, p. 426 .
- ^ A b c Walter Schumann: Precious stones and gemstones. All kinds and varieties. 1900 unique pieces . 16th, revised edition. BLV Verlag, Munich 2014, ISBN 978-3-8354-1171-5 , pp. 184 .
- ↑ Hsihutsunite. In: mindat.org. Hudson Institute of Mineralogy, accessed July 14, 2019 .
- ↑ Localities for Rhodonite. In: mindat.org. Hudson Institute of Mineralogy, accessed July 15, 2019 .
- ↑ Find location list for rhodonite at the Mineralienatlas and at Mindat
- ↑ The Rhodonite. In: heilsteine-lexikon.info. Archived from the original on June 28, 2018 ; accessed on July 14, 2019 .
- ↑ Rhodonite gemstone. In: lexikon-alternativ-heilen.de. July 10, 2018, accessed July 14, 2019 .