Celestine (mineral)
| Celestine | |
|---|---|
 |
|
| General and classification | |
| other names |
|
| chemical formula | Sr [SO 4 ] |
|
Mineral class (and possibly department) |
Sulphates, arsenates, vanadates - anhydrous sulphates with no foreign anions |
|
System no. to Strunz and to Dana |
7.AD.35 ( 8th edition : VI / A.09) 03/28/01/02 |
| Similar minerals | Anglesite , barite , Hashemit , Kerstenit |
| Crystallographic Data | |
| Crystal system | orthorhombic |
| Crystal class ; symbol | orthorhombic-dipyramidal; 2 / m 2 / m 2 / m |
| Space group | Pnma (No. 62) |
| Lattice parameters | a = 8.36 Å ; b = 5.35 Å; c = 6.85 Å |
| Formula units | Z = 4 |
| Frequent crystal faces | {001}, {010}, {011}, {101}, {210} |
| Physical Properties | |
| Mohs hardness | 3 to 3.5 |
| Density (g / cm 3 ) | 3.9 |
| Cleavage | {001} perfect, {210} imperfect |
| Break ; Tenacity | shell-like, brittle, uneven |
| colour | colorless, white, yellowish, predominantly shades of blue (name!) |
| Line color | White |
| transparency | transparent to translucent |
| shine | Glass gloss, pearlescent |
| Crystal optics | |
| Refractive indices |
n α = 1.619 to 1.622 n β = 1.622 to 1.624 n γ = 1.630 to 1.632 |
| Birefringence | δ = 0.011 |
| Optical character | biaxial positive |
| Axis angle | 2V = measured: 50 ° to 51 °; calculated: 54 to 58 ° |
Coelestin (English Celestine ), outdated also known as Cölestin , Celestine or less often as Schützite or Schätzite , is a frequently occurring mineral from the mineral class of " sulfates ( and relatives )". It crystallizes in the orthorhombic crystal system with the composition Sr [SO 4 ], so it is chemically a strontium sulfate .
Celestine usually develops prismatic or tabular crystals in the centimeter range, but crystal sizes of up to one meter have also been found.
With baryta (Ba [SO 4 ]) Coelestin forms a mixed batch with freely exchangeable strontium - or barium - ions .
Etymology and history
The mineral was already known in the 18th century, but was still considered barite or barite in 1781. It was not until an analysis carried out by Martin Heinrich Klaproth in 1797 that it was a matter of a strontium-containing material, which he called strontium earth. A year later, Abraham Gottlob Werner coined the name Coelestin, which is still valid today, for the mineral, after the Latin word coelestis for sky blue, as it is very often found in this characteristic color. In later works Werners also the spelling is Celestine and other mineralogical records among other things, the spelling Celestine . However, the spelling Celestine has established itself in specialist circles.
The type locality is Bell's Mill near Bellwood in Blair County in the US state of Pennsylvania.
classification
In the meanwhile outdated, but still in use 8th edition of the mineral classification according to Strunz , the celestine belonged to the mineral class of "sulfates (selenates, tellurates, chromates, molybdates, wolframates)" and to the department of "anhydrous sulfates without foreign anions ", where he together with Anglesit , Baryt and Hashemit the independent "Barytgruppe" formed.
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and is used by the International Mineralogical Association (IMA), also assigns Celestine to the class of "sulfates (selenates, tellurates, chromates, molybdates and wolframates)" and there in the department of “Sulphates (selenates etc.) without additional anions, without H 2 O”. However, this section 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 large cations", where, together with angelsite, barite and olsacherite, the still existing " barite group" with the system no. 7.AD.35 forms.
The systematics of minerals according to Dana assigns the celestine to the class of "sulfates, chromates and molybdates" (including selenates, tellurates, selenites, tellurites, sulfites) and there into the "sulfates" class. Here it is together with barite and angelsite in the "barite group" with the system no. 03/28/01 to be found in the subsection of " Anhydrous acids and sulfates (A 2+ ) XO 4 ".
Crystal structure
Celestine crystallizes orthorhombically in the space group Pnma (space group no. 62) with the lattice parameters a = 8.36 Å ; b = 5.35 Å and c = 6.85 Å and 4 formula units per unit cell .
properties
In its pure form, Celestine is colorless and transparent. Multiple light refraction due to polycrystalline formation or twinning also makes it appear white. By lattice defects occur in the Celestite color centers that give the crystal its characteristic bluish color. Often these centers are additionally stabilized by the presence of K + ions. Heating to over 200 ° C "heals" these structural defects and the mineral loses its color. Irradiation with X-rays creates new or more lattice defects and the color returns or can be intensified. Due to the addition of sulfur , Celestine can also have a yellowish color.
In front of the soldering tube , Celestine melts into a white pearl, coloring the flame in a characteristic carmine red .
Modifications and varieties
As Barytocoelestin or simply barium -Coelestin a barium Coelestin- will variety having the formula (Sr, Ba) [SO 4 ] indicates that as a mixed crystal between celestite and barite can be considered.
Under the name Schützite , which was coined by Karsten around 1800 , different variants of celestine were summarized, which, depending on the crystal or aggregate shape , were more precisely referred to as dense, flaky, fibrous or radiant schützite .
Education and Locations
Celestine often formed around 65 million years ago in the geological age of the Tertiary in crevices and cavities of sedimentary rocks (namely limestones , marl ) or evaporites and mostly associated with anhydrite , gypsum , halite and / or sulfur . In cavities in carbonate rocks, the mineral often occurs together with calcite , dolomite , fluorite and strontianite, as well as anhydrite and gypsum. It is rarely found in hydrothermal corridors and in bladder spaces of volcanic rocks accompanied by analcime , natrolite , hydroxyapophyllite and celadonite .
As a frequent mineral formation, Celestine can be found in many localities, whereby worldwide (as of 2013) over 1000 localities are known to be known.
The sulfur deposits near Tarnobrzeg in Poland and Caltanissetta in Italy, where prismatic crystals of up to 10 centimeters in length came to light, became particularly well-known due to extraordinary Coelestin finds. Well-developed, transparent coelestin crystals of bright blue color and up to 15 centimeters in size were found in the "Sakoany" deposit ( Boeny region ) in Madagascar, and crystals up to 30 centimeters in size were found in the municipality of Múzquiz in the Mexican state of Coahuila . In 1897, the German winery owner Gustav Heineman found a large limestone cave about 10 meters deep in Put-in-Bay on Bass Island in Ottawa County (Ohio, USA), which was lined with coelestin crystals up to 18 inches (45.7 cm) in size is. The largest known coelestins to date, striking blue stalactites of up to one meter in length, were discovered in the Argentine province of Neuquén .
In Germany, the mineral could be found in the Clara mine in Baden-Württemberg, in Wirmsthal and Ottenhäuser Grund near Schweinfurt in Bavaria, on the soldiers bush near Gembeck in Hesse, in several places near Göttingen and Bad Lauterberg in Lower Saxony, in the Münsterland and in Giershagen in Sauerland in North Rhine-Westphalia, at Ettringer Bellerberg and near Imsbach in Rhineland-Palatinate, in the limestone mine of Rüdersdorf near Berlin , in several places in Saxony-Anhalt, in the Güte Gottes mine at Bruchertseifen in Rhineland-Palatinate and near Göschwitz in Thuringia .
The only large, but now exhausted, Celestine deposits were near Giershagen in the eastern Sauerland, where around 10,000 tons of pure Celestine of special quality were discovered around 1900, and near Gembeck in the Hessian district of Waldeck-Frankenberg, which was still being mined in the 1920s .
In Austria, Celestine was found in many places in Carinthia (Friesach, Hüttenberg, Gailtaler and Carnic Alps), Salzburg (Abtenau, Murwinkel, Leogang), Styria , Tyrol (Inntal) and Upper Austria (Kirchdorf, Steyr-Land).
In Switzerland, the mineral appeared at several sites in the cantons of Aargau , Bern , Freiburg , Solothurn , Vaud and Valais .
Other sites are found in Afghanistan, Egypt, Algeria, the Antarctic, Argentina, Australia, the Bahamas, Belgium, Bolivia, Bulgaria, China, the Democratic Republic of the Congo, France, Greece, Greenland, India, Iran, Ireland, Japan, Canada, Kazakhstan, Qatar, Kyrgyzstan, Latvia, Libya, Malawi, Morocco, Mongolia, Namibia, New Zealand, the Netherlands, Norway, Oman, Portugal, Russia, Sweden, Slovakia, Slovenia, Spain, South Africa, Tajikistan, Czech Republic, Tunisia, Turkey, Turkmenistan, Ukraine, Hungary, Uzbekistan, United Kingdom (Great Britain), many US states and Vietnam.
Celestine could also be detected in rock samples from the moon , more precisely from the landing point of the Luna 16 mission.
use
As a raw material
Along with strontianite, celestine is an important ore for the extraction of strontium , even if it is only used technically to a limited extent in its pure form. As an alloying element in steel , it serves, among other things, to remove sulfur and phosphorus (see also Strontium use ).
At the end of the 19th century , Celestine was promoted in addition to strontianite for the extraction of strontium hydroxide , which was used for the residual desugarization of molasses . There is a former celestine mining site near Jena . Celestine is also necessary for the production of dyes, colored glass and electric batteries.
In contrast to the strontium sulfate Celestine, the compounds strontium nitrate , strontium oxide and strontium bromide are of greater importance. Strontium nitrate colors the flame of fireworks and signal rockets bright red, strontium oxide is used to reduce X-ray radiation in the glass of screen tubes and strontium bromide as a sedative.
The annual world production of strontium ores (Celestine and Strontianite ) is currently around 140,000 tons.
In living beings
In the case of radiolarians , the spherical skeleton can consist of silicic acid and strontium sulfate.
As a gem
Despite its appealing color and often water-clear, glass- shining crystals, Celestin is actually unusable for commercial use as a gemstone due to its low Mohs hardness of 3 to 3.5, its high tendency to split and its sensitivity to acids (body sweat attacks the stone surface) . For collectors it is nevertheless occasionally in various facets forms sanded or drum stones and Handschmeichlern processed.
See also
literature
- 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. 659 .
- 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. 70 .
Web links
- Mineralienatlas: Coelestin and Mineralienatlas: Mineralienportrait / Cölestin (Wiki)
- Celestine search results. In: rruff.info. Database of Raman spectroscopy, X-ray diffraction and chemistry of minerals (RRUFF), accessed March 10, 2019 .
- American-Mineralogist-Crystal-Structure-Database - Celestine. In: rruff.geo.arizona.edu. Retrieved March 10, 2019 .
Individual evidence
- ^ David Barthelmy: Celestine Mineral Data. In: webmineral.com. Accessed March 10, 2019 .
- ^ A b c 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. 369 (Celestine).
- ^ A b Helmut Schrätze , Karl-Ludwig Weiner : Mineralogie. A textbook on a systematic basis . de Gruyter, Berlin; New York 1981, ISBN 3-11-006823-0 , pp. 575-576 .
- ↑ a b c d e f Celestine. In: mindat.org. Hudson Institute of Mineralogy, accessed March 10, 2019 .
- ↑ Mineral Atlas: Mineral Records
- ↑ Hans Lüschen: The names of the stones. The mineral kingdom in the mirror of language . 2nd Edition. Ott Verlag, Thun 1979, ISBN 3-7225-6265-1 , p. 350 .
- ^ Type locality Bell's Mill, Bellwood, Blair Co., Pennsylvania, USA. In: mindat.org. Hudson Institute of Mineralogy, accessed March 10, 2019 .
- ^ Friedrich Klockmann : Klockmanns textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 597-598 (first edition: 1891).
- ↑ Georg Adolph Suckow : The beginnings of physics and chemistry based on the latest discoveries. In two parts . II. And last part. Chemistry. CH Stagesche Buchhandlung, Augsburg, Leipzig 1814, p. 266 ( limited preview in Google Book Search [accessed March 10, 2019]).
- ↑ Celestine . 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; 67 kB ; accessed on March 10, 2019]).
- ↑ Petr Korbel, Milan Novák: Mineral Encyclopedia (= Dörfler Natur ). Edition Dörfler im Nebel-Verlag, Eggolsheim 2002, ISBN 978-3-89555-076-8 , p. 138 .
- ↑ The Giant Crystal Project Site - Coelestin ( Memento of August 23, 2012 in the Internet Archive )
- ↑ Giershagen mining traces. Flatly. North route: 33 Cölesting mine. In: bergbauspuren.de. Friends of “Our Giershagen” eV, accessed on March 10, 2019 .
- ↑ a b List of localities for Celestine in the Mineralienatlas and Mindat
- ↑ Rainer Müllan: microscopy ; Tribe: Rhizopoda, order: Radiolaria ( Memento from November 10, 2013 in the Internet Archive )
- ^ Gemstone etiquette by Prof. Leopold Rössler: Cölestin. In: beyars.com. BeyArs, accessed March 10, 2019 .
- ^ 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. 224 .