Witherit

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Witherit
Witherite-48305.jpg
Witherite from the district of Alston Moor (Cumberland), England
General and classification
other names
  • Terra ponderosa aërata
  • Aerated Barytes
  • Barolite
  • Carbonic barite
  • Baryte carbonate
  • Sulphato-Carbonates of Barytes
  • Carbonic barite
  • Witheritspat
chemical formula Ba [CO 3 ]
Mineral class
(and possibly department) 		Carbonates and nitrates - carbonates without additional anions; without H 2 O
System no. to Strunz
and to Dana 		5.AB.15 ( 8th edition : Vb / A.04)
01/14/03/02
Similar minerals Cerussite , quartz
Crystallographic Data
Crystal system orthorhombic
Crystal class ; symbol orthorhombic-dipyramidal; 2 / m  2 / m  2 / m
Space group Pmcn (No. 62, position 5)Template: room group / 62.5
Lattice parameters a  = 5.312  Å ; b  = 8.896 Å; c  = 6.428 Å
Formula units Z  = 4
Frequent crystal faces {110}, {021}, {001}, {111}
Twinning Penetration triplets according to (110)
Physical Properties
Mohs hardness 3 to 3.5
Density (g / cm 3 ) 4.22 to 4.31 (measured); 4.24 to 4.29 (calculated)
Cleavage clear after {010}, indistinct after {110} and {112}
Break ; Tenacity uneven; brittle
colour colorless, white, gray with occasional pale yellow, pale brown, or pale green tinge; colorless in transmitted light
Line color White
transparency translucent to translucent
shine Glass gloss or matt, on broken surfaces resin gloss or fat gloss
Crystal optics
Refractive indices n α  = 1.529
n β  = 1.676
n γ  = 1.677
Birefringence δ = 0.148
Optical character biaxial negative
Axis angle 2V = 16 °
Other properties
Chemical behavior Easily soluble in dilute HCl with bubbles
Special features harmful to health; fluoresces and phosphoresces under UV, electron and X-ray radiation

Witherite is a rather seldom occurring barium carbonate - mineral from the mineral class " carbonates and nitrates " (formerly carbonates, nitrates and borates ). It crystallizes in the orthorhombic crystal system with the idealized chemical composition Ba [CO 3 ], so it is chemically seen a barium - carbonate .

Due to the formation of twins, Witherite mainly develops dipyramidal, pseudo-hexagonal crystals up to 12 cm in size, more rarely also grape to spherical, columnar-fibrous, granular or massive mineral aggregates , which can be either colorless or white, gray or yellowish in color due to impurities.

The type locality of the Witherite is the "Bloomsberry Horse Level" of the "Brownley Hill Mine" ( coordinates of the Brownley Hill Mine ) at Nenthead in the Civil Parish Alston Moor , Eden District , Cumbria County in England in the United Kingdom .

Etymology and history

The mineral was first mentioned in 1783 by William Withering , a British botanist and doctor , in a footnote in his translation of the “Sciagraphia Regni Mineralis” by Torbern Olof Bergman as Terra Ponderosa aërata : “I have lately discovered a specimen of terra ponderosa aerata got out of a mine in this kingdom. It is very pure and in a large mass. "

The Witherit was first described by William Withering in 1784 in the Philosophical Transactions of the Royal Society of London :

William Withering - namesake for the withit

“This substance was got out of a lead-mine at Alston-Moor, in Cumberland. I first saw it in the valuable collection of my worthy and ingenious friend Matthew Boulton , Esq. at Soho; who, when he picked it up; conjectured from its weight that it contained something metallic. About two years ago I saw it in his possession; and partly from its appearance, being different from that of any calcareous spar I had seen, and partly from its great weight, I suspected it to be the spatum ponderosum. "

“This substance was extracted from a lead mine in Alston-Moor in Cumberland. I saw it for the first time in the precious collection of my worthy and brilliant friend Matthew Boulton , Esq., In Soho, who, when he picked it up, suspected from its weight that it contained something metallic. I saw it in his possession about two years ago, partly because of its appearance, which was different from any calcareous spar I've ever seen, and partly because of its heavy weight, I suspected it was the Spatum Ponderosum. "

- William Withering & Richard KIrwan : Experiments and Observations on the Terra Ponderosa (1784)
Oral hole of the Horse Level of the "Brownley Hill Mine" near Alston Moore - the type locality for the withitite

The view that Withering's stage came from Anglezarke , Lancashire rather than Alston Moore, came from James Watt Jr., who called it Aerated Barytes and wrote: “However, he [Withering] got wrong about the place where the stage came from informed. He guessed it was Alston Moore, but to my knowledge such material was never found there. Since then, he has informed me that he believes the specimen is from the same Anglezark mine that is the subject of this report. ”Watt's authority to contest the Witherite occurrence at Alston Moor is questionable because of its occurrence has long been known. The change of heart of Withering itself regarding the origin of its material seems to have been just a change of belief. A final solution to the problem is obviously not possible - the assumption of Anglezark (e) as the type locality of the withite is much more questionable than that of Alston Moor.

As early as 1789, Abraham Gottlob Werner named this substance Witherite in honor of William Withering . A year later he said: “I have also recently [...] the ones from Dr. Withering in England discovered a new genus of the heavy earth family, namely heavy earth saturated with air acid, named Witherite in his honor as inventor and researcher ... “The Irish chemist Richard Kirwan had described the mineral as barolite in 1794 , the Scottish chemist Thomas Thomson described it in 1836 - without going into the long-known “Witherite”, which has been established as an independent mineral - as Sulphato-Carbonate of Barytes .

Type material of the mineral, regardless of the first description by Werner, is neither contained nor defined in the "Werner Collection" within the "Geoscientific Collections" at the Technical University Bergakademie Freiberg in Freiberg , Saxony , Germany , as is the " Type Mineral Catalog Germany" shows.

classification

In the 8th edition of the mineral classification according to Strunz , witherite belonged to the common mineral class of "carbonates, nitrates and borates" and there to the department of "carbonates", where together with alstonite , aragonite , cerussite and strontianite it belongs to the "aragonite series" the system no. Vb / A.04 within the subsection “Anhydrous carbonates without foreign anions ”.

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 outdated system of Karl Hugo Strunz , the mineral received the system and mineral number. V / B.04-30 . In the "Lapis system" this corresponds to the section "Anhydrous carbonates [CO 3 ] 2- , without foreign anions", where Witherite together with alstonite, aragonite, barytocalcite , cerussite, olekminskite , paralstonite and strontianite also form the "aragonite group" (v /B.04) forms.

The 9th edition of Strunz's mineral systematics, which has been in force since 2001 and updated by the International Mineralogical Association (IMA) until 2009, assigns witherite to the class of “carbonates and nitrates”, which has been reduced by the borates, and then to the “carbonates without additional” class Anions; without H 2 O “. This is further subdivided according to the group affiliation of the cations involved , so that the mineral can be found according to its composition in the subsection "alkaline earth (and other M 2+ ) carbonates", where it is only together with aragonite, cerussite and strontianite the " Aragonite group "with the system no. 5.AB.15 forms.

The systematics of the minerals according to Dana classifies the witherite like the old Strunz'sche systematics in the common class of "carbonates, nitrates and borates" and there in the department of "anhydrous carbonates". Here it is together with aragonite, cerussite and strontianite in the "aragonite group (Orthorhombic: Pmcn )" with the system no. 01/14/03 to be found in the subsection of " Anhydrous carbonates with simple formula A + CO 3 ".

Chemism

Microprobe analyzes on Witherite from Anglezarke in Lancashire revealed 77.15% BaO; 0.08% CaO; 0.68% SrO; 22.50% CO 2 (calculated from the stoichiometry) and 0.0% PbO (total 100.41%). On the basis of 3 oxygen atoms, the empirical formula (Ba 0.99 Sr 0.01 ) Σ = 1.00 CO 3 is calculated, which can be idealized to BaCO 3 . This idealized formula requires 77.70% BaO and 22.30% CO 2 .

Other analyzes (e.g. in Arthur Baldasari & J. Alexander Speer 1979) show that witherite is mostly pure BaCO 3 . In significant amounts, barium is only substituted by strontium (maximum 6.06% SrO), calcium can also be present, but only to a very minor extent. Occasionally, low levels of iron and sulfate have been detected. Lead and magnesium are not included in the existing analyzes.

The only combination of elements Ba – C – O among the currently known minerals shows only witherite. Alstonite , paralstonite and barytocalcite are chemically similar , all BaCa (CO 3 ) 2 ; and Norsethit , BaMg (CO 3 ) 2 . From a chemical point of view, Witherite is the barium-dominant analogue of Ca-dominated aragonite, Sr-dominated strontianite and Pb-dominated cerussite. Complete rows of mixed crystals between BaCO 3 and PbCO 3 were experimentally detected - but only above relatively high temperatures. In the CaCO 3 -SrCO 3 -BaCO 3 system , the aragonite structure type forms a complete mixed crystal series at 15 kbar and 550 ° C, starting from BaCO 3 via SrCO 3 to CaCO 3 . In nature there is no complete series of mixed crystals between Witherite and Strontinanite. This miscibility gap results either from the difference between the ionic radii of barium (135 pm) and strontium (118 pm) or from the fact that fluids from which both Sr and Ba can be precipitated together do not exist.

Crystal structure

Spatial representation of the structure of witherite in the standard crystallographic orientation. The black outline shows the unit cell. Color legend:    __ Ba __ C __ O

Witherite crystallizes in the orthorhombic crystal system in the space group Pmcn (space group no. 62, position 5) with the lattice parameters a = 5.312  Å , b = 8.896 Å and c = 6.428 Å as well as four formula units per unit cell . The crystal structure of the witherite was first determined in 1935 and has been refined several times since then. The most modern work comes from Yu Ye, Joseph R. Smyth and Paul Boni - the spatial representation of the witherite structure was drawn based on their data. BaCO 3 is polymorphic . The rhombic witherite is converted at 802 ° C in hexagonal BaCO 3 and this at 975 ° C in cubic BaCO 3 to. The decomposition of witherite or BaCO 3 at high temperatures to either a melt or to BaO + CO 2 depends on the pressure of the carbon dioxide . At temperatures of 1060 ° C. and CO 2 partial pressures of around 670 Pa, the dissociation of the BaCO 3 is accompanied by the melting of the oxide formed with the remaining carbonate to form a melt. Below this temperature the BaCO 3 decomposes to BaO and CO 2 . Template: room group / 62.5

In the crystal structure of witherite, which corresponds to that of aragonite and resembles that of calcite, there are triangular CO 3 groups in the (001) plane arranged in pairs, rotated by 60 ° and connected to one another by M [9] cations , in the case of withit, that is, by nine-coordinate Ba 2+ cations. In other words, layers with Ba 2+ ions follow in the direction of the c-axis [001] layers with almost planar, triangular [CO 3 ] 2− groups. A comparison of the aragonite and the calcite structure shows that there are shifts in the bivalent positive ions such as Ba 2+ in relation to the lattice sites of the calcite structure and the splitting of the [CO 3 ] 2− layers into double layers in and with the aragonite Isotypic connections lead to a change in the coordination relationships. While in the calcite structure each Ca 2+ ion is octahedrally surrounded by six oxygen ions, in the aragonite structure there are irregular coordination polyhedra made up of nine O 2− ions.

Witherite is isotypic (isostructural) with its Ca, Sr and Pb analogues aragonite, strontianite and cerussite.

properties

morphology

Witherite is seldom easy, according to the c-axis [001] in the short to long prismatic crystals to the dress the prisms {110}, {011}, {012} and {021}, the Basispinakoid {001} and the pinacoid { 010} as well as the rhombic dipyramid {111} belong. Much more common are the penetration triplets, which are formed by the almost constant formation of twins according to (110) and are reminiscent of quartz dipyramids (high quartz, quartz-beta) and reach sizes of up to 15 cm. The twins consist of countless fine lamellae, so they represent polysynthetic twins. These pseudo-hexagonal twins also vary in habit from short to long prismatic along the c-axis, with the former having a prism parallel to the a-axis such as {012} or {021} , in the latter case the pinacoid {010} is decisive. Finally, there are also tabular, spindle-shaped to barrel-shaped and, thanks to a convex base, even lenticular twin crystals. The morphology of the witherite twin crystals is often "complex and obscure". The crystal surfaces are rough and horizontally striped by etching.

  • Costume and habitus of withitherite crystals

  • short prismatic flat panel

  • flat, almost lenticular

  • long prismatic and very glossy glass

  • short prismatic, with a large base pinacoid and strongly stepped

  • quartz-like triplets

  • divergent aggregate, green color from nickel

  • barrel-shaped crystal

  • almost spherical aggregate with strongly curved surfaces

Are known epitaxial (oriented) adhesions with baryta such that barite comes to lie with [010] {102} parallel to witherite [100] {011} and {031}.

Witherite is also coarse and develops grape-kidney to spherical (collomorphic), rayy-coarse-fiber, granular or massive mineral aggregates.

physical and chemical properties

Fluorescence of a withite from the “Mahoning No. 1 Mine “near Cave-in-Rock, Illinois / USA
Witherite-Fluorite-182986.jpg
Recording in daylight / artificial light
Witherite-Fluorite-182987.jpg
same level, fluorescent light blue in UV light

The crystals of Witherite are colorless, (milky) white or gray with an occasional pale yellow, pale brown or pale green tinge. Their line color , however, is always white. The surfaces of the translucent to transparent crystals show a characteristic glass-like luster or are matt due to etching. Witherit is glossy or greasy on broken surfaces. According to this glass gloss, Witherite has a medium-high light refraction ( n α  = 1.529; n β  = 1.676; n γ  = 1.677) and very high birefringence (δ = 0.148). In transmitted light, the biaxial negative witherite is colorless and shows no pleochroism.

Witherite has a clear cleavage according to {010} and two indistinct cleavages according to {110} and {112}. Due to its brittleness , however , the mineral breaks like amblygonite , with the fracture surfaces being uneven. Witherite has a Mohs hardness of 3 to 3.5 and is one of the medium-hard minerals that, like the reference mineral calcite (hardness 3), can be scratched more or less easily with a copper coin. The measured density for Witherite is 4.22 to 4.31 g / cm³, depending on the author, the calculated density is 4.24 to 4.29 g / cm³.

Witherit shows strong bluish-white fluorescence in long-wave UV light (365 nm ), while medium-strong bluish-white or violet-blue fluorescence occurs in short-wave UV light (254 nm). At least part of the activity is caused by the activator Eu 2+ , which enters the crystal lattice for the Ba 2+ . The phosphorescence of the mineral was described as early as 1903. A strong bluish-white phosphorescence can be seen in both short and long-wave UV light. Witherite also fluoresces and phosphoresces under X-rays and electron beams (e.g. under the electron beam of the microprobe ). The mineral is also thermoluminescent .

The mineral dissolves completely in dilute hydrochloric acid , HCl, with a brisk shower, but not in concentrated HCl. In dilute sulfuric acid , H 2 SO 4 , also easily soluble with immediate precipitation of barium sulfate . Witherit is only slightly water-soluble and not hygroscopic (water-attracting). Witherite melts to a pearl in front of the soldering tube , burns alkaline and colors the flame clearly yellowish green. When mixed with soda, it also melts very easily and is drawn into the coal. This penetrated mass, on a silver sheet moistened with water, does not give a hepar reaction as soon as the mineral and the soda are free of sulfuric acid.

Education and Locations

Educational conditions

Witherite and alstonite from the Brownley Hill Mine near Nenthead, Cumbria, England
Alstonite-Witherite-oldeuro-107a.jpg
View of the entire 9.7 × 4.1 × 3.7 cm step
Alstonite-Witherite-oldeuro-107c.jpg
Detail: witherite aggregate on alstonite
Alstonite-Witherite-oldeuro-107d.jpg
Alstonite crystals form the witherite matrix
Alstonite-Witherite-oldeuro-107b.jpg
Label and description for the level shown above

Witherite forms in deep thermal, i.e. low-temperature, dike deposits as well as hydrothermal displacement deposits of limestone , typically as an alteration product of barite. In particular in the deposits in the north of England, these tunnels run through carbonaceous rocks. Accompanying minerals include barite , fluorite and calcite as well as galena and sphalerite . In addition, it also arises contact metasomatically during the intrusion of large plutons, with the adjacent rock in the area of ​​the contact zone of the pluton being overprinted by heating and interactions with hot, aqueous fluid phases, with new minerals such as e.g. B. Witherite are formed. The most important of these deposits is the barium deposit discovered in the 1880s in the "El Portal Mine" near El Portal in Mariposa County in California / USA . Can also form sediment under anoxic conditions, with the barium being supplied by volcanic hot springs. Rarely also in coal seams.

In addition to the minerals already mentioned, Witherite can also be accompanied by Alstonite , Barytocalcite , Siderite , Paralstonite and Strontianite .

As a rather seldom occurring mineral formation, which can sometimes be abundant at different sites, but overall is not very widespread, the witherite has been described by around 250 sites so far (as of 2019). The type locality of Witherits is the "Bloom Berry Horse Level" of "Brownley Hill Mine" at Nenthead in the municipality ( Civil Parish ) Alston Moor , district of Eden , County of Cumbria in England in the UK . This pit is also type locality for Alstonite (1841) and Brianyoungite (1993).

Locations

In view of the large number of sites where Witherite was found, only a few localities that produce beautiful crystals can be mentioned here. The most beautiful witherite stages were found in various locations in England ("Rampgill Mine" and other pits in the Alston Moor District) and Wales (road cut near Llantrisant), in the Rosebery Mine in Tasmania and in particular the "Minerva # 2 Mine" near Rosiclare not far Cave-in-Rock recovered from Hardin Co. in Illinois / USA.

The best witherites in Germany come from the Beryl corridor, -1305 m bottom of shaft 371, Schlema-Hartenstein district, Erzgebirgskreis , Saxony . In Saxony also from the "Himmelsfürst Fundgrube" near Brand-Erbisdorf , Freiberg Revier, both in the Ore Mountains , as well as the "Ludwig-Vereingt Feld" near Schönbrunn near Oelsnitz in Vogtland and the Cu-Pb-Ag mining district of Wolkenburg near Limbach-Oberfrohna in the district of Zwickau . In Lower Saxony from the “Prinz Maximilian” mine near Sankt Andreasberg in the mining area of ​​the same name and the “Glückauf” mine (Hüttschentaler Gang) in the Hüttschental near Wildemann , Bad Grund not far from Clausthal-Zellerfeld , both in the Harz Mountains . Furthermore from slag heaps at the Richelsdorfer Hütte near Suss not far from Nentershausen in the Richelsdorf district ( Richelsdorfer Gebirge ), Hesse .

In Austria , Witherite was found on slag heaps near Waitschach not far from Hüttenberg , Friesach-Hüttenberg region; at Strabaleben in the Wurten, Innerfragant , Goldberg group in the Hohe Tauern ; as well as in the “Paule” quarry, Mairist on the northwest slope of the Magdalensberg massif not far from Klagenfurt , all found in Carinthia . Also on slag heaps near Kolm-Saigurn such. B. the "Astenschmiede" in the area Alteck- Hoher Sonnblick , Hüttwinkltal, Raurisertal , Hohe Tauern, and from the Schwarzleograben in the district Schwarzleo, huts near Leogang not far from Saalfelden , both in Salzburg . From iron mining and the "Sommerhalt" mine (Schüttereck), Gollrad , and the "Sohlen Alp" in Niederalpl, all not far from Mariazell , the "Steinbauergrube" near Neuberg an der Mürz and the Pb-Zn mining district "Elisabeth" near Deutschfeistritz and the Arzwaldgraben near Waldstein , both not far from Peggau , all in Styria . In Tyrol from “St Gertraudi”, Brixlegg - Rattenberg , as well as in the “Revier Ringenwechsel” near Schwaz , both in the Brixlegg-Schwaz area, Inntal in North Tyrol. Locations from Switzerland are unknown.

In addition to the type locality for Witherite, the "Brownley Hill Mine" (Bloomsberry Horse Level), there are also a number of other locations for this mineral in Great Britain . These include:

Witherit from the "Settlingstones Mine" near Newbrough in the Tyne Valley, Northumberland, England. Step size: 14.5 × 7.0 × 5.9 cm
Witherite from the “Pigeon Roost Mine” near Glenwood, Montgomery Co., Arkansas / USA. Step size: 12.9 × 12 × 5.5 cm

Other well-known sites for Witherite are:

Other locations are in South Australia in Australia; Chongqing , Hubei , Shaanxi and Sichuan in China; Sardinia in Italy ; Katanga in the Democratic Republic of the Congo ; Baja California in Mexico ; Siberia in Russia; Banská Bystrica , Košice and Žilina in Slovakia ; Limpopo in South Africa ; Namibia (the Tsumeb Mine) ; Moravia in the Czech Republic and in the USA.

Precautions

Like all water- or acid-soluble barium compounds, witherite, especially witherite dust, is poisonous. Due to the release of barium ions in acids, and thus also in gastric acid , with Witherit there is a risk of damage to health, especially through accidental ingestion. This can lead to muscle paralysis and damage to the heart, central nervous system and gastrointestinal tract. Inhaling withitherite dust causes irritation of the respiratory tract. Absorption into the body ( incorporation or ingestion ) should therefore be prevented in any case and the relevant safety instructions when handling Witherit should be observed. This includes avoiding inhalation of the dust that arises from grinding, sawing or cutting witherite steps and cleaning hands after handling witherite samples. Because of its toxicity, barium carbonate has been used as a rat poison.

use

Witherite is a barium raw material and is mined in many deposits together with barium as barium ore. In terms of quantity, however, it is far less than barite. Barium is used as a highly reactive getter material (Ba-Al alloy with 55% barium and 45% aluminum in, for example, X-ray and transmitter tubes, where it binds the last traces of the air gases oxygen, nitrogen , carbon dioxide and water vapor . By reacting barium carbonate Barium sulphate precipitated with sulfuric acid is called "Blanc fixe", is inert , lightfast and ultraviolet-proof and is used in the paint and plastics industry as a white pigment and as an inexpensive extender for titanium dioxide . It is used in the production of high-quality art, drawing and photo papers. Barium titanate is ferro- and piezoelectric , has a high dielectric constant and is therefore used as a transducer for ultrasonic transmitters , as a dielectric in capacitors and as a material for electrets . Bismuth- doped barium titanate is a PTC thermistor that is a good electrical conductor when cold but has a much higher specific resistance un d is therefore used as a current limiter. Barium ferrites are important permanent magnetic materials and are u. a. used in speakers and magnetic adhesive strips. Barium compounds such as barium cuprates of lanthanum and yttrium were among the first high-temperature superconductors . In 1988, a superconductor made of thallium- calcium-barium-cuprate reached a record transition temperature of 125 K (−148 ° C), which was not exceeded until 1993.

Due to its gemological characteristics (color, transparency, refractive indices, hardness and size of the crystals), witherite is rarely ground. Faceted stones are more of a collector's item, with even stones under 5 carats more translucent than transparent. One of the larger cut Witherite is a 8.36 ct stone with the dimensions 1.38 mm × 0.91 mm × 0.66 cm. Witherit is preferably cut in the shapes of "octagon", "triangle" ("trilliant cut") and "square" ("cushion cut"). Images of smoothed Witherite can be seen at RealGems.org and gemdat.org. In addition, Witherite is a sought-after mineral by mineral collectors.

See also

literature

Web links

Commons : Witherite  - collection of images, videos and audio files

Individual evidence

  1. ^ A b c William Withering , Richard Kirwan : Experiments and Observations on the Terra Ponderosa . In: Philosophical Transactions of the Royal Society of London . tape  74 , 1784, pp. 292–311 , doi : 10.1098 / rstl.1784.0024 (English, rruff.info [PDF; 1.4 MB ; accessed on September 17, 2019]).
  2. ↑ a b James Watt Jr .: Some account of a mine in which the Aerated Barytes is found . In: Memoirs of the Literary and Philosophical Society of Manchester . tape 3 , 1790, pp. 599–608 (English, limited preview in Google Book Search).
  3. ↑ a b Richard Kirwan : Elements of Mineralogy: Vol. I. Earths and Stones . 2nd with considerable improvements and additions edition. J. Nichols, London 1794, p.  134–136 (English, sachsen.digital [PDF; 105 kB ; accessed on September 17, 2019]).
  4. ^ A b Thomas Thomson : Outlines of Mineralogy, Geology, and Mineral Analysis (Vol. 1) . Baldwin & Cradock, London 1836, p.  106–107 (English, limited preview in Google Book Search).
  5. ↑ a b Hans Leitmeier : Barium carbonate Ba (CO 3 ). Witherit . In: Cornelio August Doelter (Ed.): Handbuch der Mineralchemie . General introduction Carbon Carbonate Silicate I. 1., Softcover-Reprint edition. tape  1 . Springer, Berlin and Heidelberg 1912, ISBN 978-3-642-49766-7 , pp. 490–501 , doi : 10.1007 / 978-3-642-49766-7 ( limited preview in Google book search).
  6. ↑ a b c d e f g h i j Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp.  575 (first edition: 1891).
  7. ↑ a b c d e f g h i j Witherite . 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; 67  kB ; accessed on September 17, 2019]).
  8. ↑ 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.  287-288 .
  9. ↑ a b c d e f g h i j k l m n o p Luke LY Chang , Robert Andrew Howie , Jack Zussman : Rock-forming minerals Vol. 5B: Mon-silicates: Sulphates, Carbonates, Phosphates and Halides . 2nd Edition. Longman, London 1996, ISBN 0-582-30093-2 , pp.  263–271 (English, limited preview in Google Book Search - first edition: 1961).
  10. ↑ a b c d e f g h i j k l m n o p q r s t u Charles Palache , Harry Berman , Clifford Frondel : Witherite . In: The System of Mineralogy . of James Dwight Dana and Edward Salisbury Dana Yale University 1837-1892. 7th edition. II (Halides Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates etc.). John Wiley & Sons, New York 1951, ISBN 0-471-19272-4 , pp.  194–196 (English, first edition: 1892).
  11. ^ William Withering : Outlines of mineralogy, translated from the original of Sir Torbern Bergman, Knight of the Order of Wasa, professor of chemistry at Upsal, & c. Cadell and Robinson, Birmingham 1783, pp.  28 .
  12. ^ J. Selwyn Turner: Short communications: The type-locality of witherite . In: Mineralogical Magazine . tape 33 , no. 260 , 1963, pp. 431–432 , doi : 10.1180 / minmag.1963.033.260.08 (English, rruff.info [PDF; 105 kB ; accessed on September 17, 2019]).
  13. ↑ Christian August Siegfried Hoffmann : Inspector Werner's mineral system with his permission, published by CAS Hoffmann . In: Bergmännisches Journal . tape  2 , no. 1 , 1790, p. 369–398 ( rruff.info [PDF; 1.9 MB ; accessed on September 17, 2019]).
  14. ↑ Abraham Gottlob Werner : Newer description of the prehnite along with some remarks about the designation assigned to it, as well as generally about the formation of some designations of natural bodies after personal names . In: Bergmännisches Journal . tape  3 , no. 1 , 1790, p. 99–112 ( limited preview in Google Book search).
  15. ↑ Typmineral catalog Germany - storage of the Witherit type level. In: typmineral.uni-hamburg.de. Mineralogical Museum of the University of Hamburg, accessed on September 23, 2019 .
  16. ↑ 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 .
  17. ↑ Ernest H. Nickel, Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF 1703 kB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed September 25, 2019 .
  18. ↑ a b c d e Arthur Baldasari, J. Alexander Speer: Witherite composition, physical properties, and genesis . In: The American Mineralogist . tape 64 , no. 7/8 , 1979, pp. 742-747 ( minsocam.org [PDF; 642 kB ; accessed on September 17, 2019]).
  19. ^ A b c Karl-Ludwig Weiner , Rupert Hochleitner: Witherit profile . In: Lapis . tape  12 , no. 5 , 1987, pp. 7-9 .
  20. ^ Minerals with Ba, C, O. In: mindat.org. Hudson Institute of Mineralogy, accessed September 23, 2019 .
  21. ↑ a b J. Alexander Speer: Crystal Chemistry and Phase Relations of Orthorhombic carbonate . In: Richard J. Reeder (Ed.): Reviews in Mineralogy Volume . Volume 11: Carbonates: Mineralogy and Chemistry. 1st edition. Mineralogical Society of America, Chelsea / Michigan 1983, ISBN 978-0-939950-15-7 , pp. 145–190 ( limited preview in Google Book search).
  22. ↑ Malcom Y. Colby, Lucien JB LaCoste: The crystal structure of witherite . In: Journal of Crystallography . tape 90 , 1935, pp. 1–7 , doi : 10.1524 / zkri.1935.90.1.1 (English).
  23. ↑ Yu Ye, Joseph R. Smyth, Paul Boni: Crystal structure and thermal expansion of aragonite-group carbonates by single-crystal X-ray diffraction . In: The American Mineralogist . tape 97 , no. 4 , 2012, p. 707–712 , doi : 10.2138 / am.2012.3923 (English, researchgate.net [PDF; 349 kB ; accessed on September 25, 2019]).
  24. ↑ EH Baker: The barium oxide-carbon dioxide system in the pressure range 0.01-450 atmospheres . In: Journal of the Chemical Society . tape 1964 , 1964, pp. 699-704 , doi : 10.1039 / JR9640000699 .
  25. ↑ Rupert Hochleitner, Henning von Philipsborn, Karl-Ludwig Weiner: Minerals: Determination of external characteristics . 3. Edition. E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart 1996, ISBN 3-510-65164-2 , p. 276-277 .
  26. ^ Karl Ludwig Felix Machatschki : Special mineralogy on a geochemical basis . 1st, softcover reprint edition. Springer, Vienna 1953, ISBN 978-3-7091-8006-8 , p.  165 , doi : 10.1007 / 978-3-7091-8006-8 ( limited preview in Google book search).
  27. ↑ a b Stefan Schorn and others: Witherit. In: mineralienatlas.de. Retrieved September 23, 2019 .
  28. ↑ a b Gerard Barmarin: Whiterite. In: fluomin.org. Luminescent Mineral Database, accessed September 23, 2019 (English, fluorescence data for Witherite).
  29. ↑ George Frederick Kunz , Charles Baskerville: The Action of Radium, Roentgen Rays and Ultra-violet Light on Minerals and Gems . In: Science . tape  18 , no. 468 , 1903, pp. 769–783 , doi : 10.1126 / science.18.468.769 , JSTOR : 1631516 (English).
  30. ^ A b Friedrich Kolbeck : Karl Friedrich Plattner's art of trying with the soldering tube . 7th edition. Johann Ambrosius Barth, Leipzig 1907, p.  121–122 (first edition: 1835).
  31. ↑ a b Data sheet barium carbonate (PDF) from Carl Roth , accessed on September 23, 2019.
  32. ^ AA Fitch: Barite and witherite from near El Portal, Mariposa County, California . In: The American Mineralogist . tape 16 , no. 10 , 1931, p. 461–468 ( minsocam.org [PDF; 453 kB ; accessed on September 17, 2019]).
  33. ↑ a b c d Whiterite. In: mindat.org. Hudson Institute of Mineralogy, accessed September 23, 2019 .
  34. ↑ Localities for Whiterite. In: mindat.org. Hudson Institute of Mineralogy, accessed September 23, 2019 .
  35. ↑ a b List of places where Witherite was found in the Mineralienatlas and Mindat (accessed on 23 September 2019)
  36. ^ David I. Green, David McCallum, Mike Wood: Famous mineral localities: The Brownley Hill Mine, Alston Moor District, Cumbria, England . In: Mineralogical Record . tape 31 , no. 3 , 2000, pp. 231-250 .
  37. ^ Brownley Hill Mine. In: mindat.org. Hudson Institute of Mineralogy, accessed September 23, 2019 .
  38. ↑ a b c d e f Lucien F. Trueb: The chemical elements: a foray through the periodic table . 1st edition. S. Hirzel Verlag, Stuttgart Leipzig 1996, ISBN 3-7776-0674-X , p. 79-81 .
  39. ^ Whiterite. In: gemsociety.org. International Gem Seciety, accessed on September 23, 2019 (English, with image examples of cut withite).
  40. ↑ a b Realgems Database - Witherite. In: www.realgems.org. Retrieved on September 23, 2019 (English, with examples of cut Witherite).
  41. ^ Whiterite. In: gemdat.org. Hudson Institute of Mineralogy, accessed on September 23, 2019 (English, with examples of cut witherite).