Bieberit
| Bieberit | |
|---|---|
 |
|
| General and classification | |
| other names |
|
| chemical formula | Co [SO 4 ] • 7H 2 O |
|
Mineral class (and possibly department) |
Sulphates (selenates, tellurates, chromates, molybdates and tungstates) |
|
System no. to Strunz and to Dana |
7.CB.35 ( 8th edition : VI / C.06) 06/29/10/04 |
| Similar minerals | Erythrin |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | monoclinic prismatic; 2 / m |
| Space group | P 2 1 / c (No. 14) |
| Lattice parameters |
a = 14.04 Å ; b = 6.50 Å; c = 10.92 Å β = 105.3 ° |
| Formula units | Z = 4 |
| Physical Properties | |
| Mohs hardness | 2 |
| Density (g / cm 3 ) | measured: 1.96; calculated: 1.942 |
| Cleavage | completely after {001}, clearly after {110} |
| colour | pink to meat red; in transmitted light, light pink to colorless |
| Line color | White |
| transparency | translucent |
| shine | Glass gloss |
| Crystal optics | |
| Refractive indices |
n α = 1.477 n β = 1.483 n γ = 1.489 |
| Birefringence | δ = 0.012 |
| Optical character | biaxial negative |
| Axis angle | 2V = 88 ° (measured and calculated) |
| Other properties | |
| Chemical behavior | water soluble, easily dehydrated to moorhouseit |
Bieberite , out of date also known as cobalt vitriol , red vitriol and rhodhalose , is a rarely occurring mineral from the mineral class of "sulfates (and relatives, see classification )" with the chemical composition Co [SO 4 ] · 7H 2 O and is therefore From a chemical point of view, a water-containing cobalt (II) sulfate , more precisely its heptahydrate .
Bieberite crystallizes in the monoclinic crystal system , but develops only tiny crystals and is mostly found in the form of stalactites or crusty coatings on other minerals. The generally translucent mineral is pinkish-red to flesh-red in color, but leaves a white line on the marking board . In transmitted light it appears rather light pink to almost colorless. The surfaces of the crystals have a glass-like sheen .
Etymology and history
The first confirmed discovery for naturally occurring cobalt vitriol was documented in 1807 for the mining area around Bieber in the Hessian Main-Kinzig district .
A discovery of cobalt vitriol that had previously been made known near the town of Špania Dolina (German: Herrengrund ), which was formerly part of Hungary , was doubted by several mineralogists such as Kirwan , Widenmann , Brochant and Haüy , because sulfuric cobalt was by far the rarest of all sulfuric metallic salts and is by far the rarest therefore difficult to analyze due to the small number and size of the samples. As a result, the results of the analysis tests were partly contradicting.
The first description was made in 1807 and somewhat more detailed in 1808 by Johann Heinrich Kopp , who called the mineral cobalt vitriol based on its chemical composition , vitriol being a common name for all sulphates of divalent metals containing water of crystallization. Kopp reports that the external characteristics were, however, already summarized in 1800 based on the samples from Herrengrund by Dietrich Ludwig Gustav Karsten in his mineralogical tables as follows:
“It has a rose-red color; stalactite shape; grained surface; is not very shiny on the outside; glossy or very glossy inside, of glass gloss; straight-leaved when broken (in one direction); semi-transparent; gives a white line; is soft; extremely mild; light and has a not very noticeable typical taste. [Note: styptisch is outdated for astringent from Greek styptikos or styphein ] "
In addition, after extensive analyzes, Kopp 1908 gives the composition with 28.71% cobalt oxide (CoO), 19.74% sulfuric acid and 41.55% water (H 2 O), which corresponds to the currently defined composition (26.66% CoO; 28, 48% SO 3 ; 44.86% H 2 O) is already quite close. He adds the following to the external description of the mineral:
“The shape [is] jagged, stalactite-like and knotty; on the surface it then appears rough and furrowed lengthways; it also appears as a crust-shaped or thin coating and when it has flown to it, as if it were foam-like and yeast-like [...] "
The mineral received its name , which is still valid today, based on its type of locality , in 1845 from Wilhelm von Haidinger .
classification
In the 8th edition of the mineral systematics according to Strunz , which is out of date, but still in use , the Bieberite belonged to the mineral class of "sulfates, chromates, molybdates, tungstates (including selenates and tellurates)" and there to the department "C. Water-containing sulfates, without foreign anions ”, where together with alpersite , boothite , mallardite , melanterite and zinc melanterite, the“ melanterite group ”with the system no. VI / C.06 .
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 Bieberite to the category of "sulfates (selenates, etc.) without additional anions, with H 2 O". However, this is further subdivided according to the relative size of the cations involved , so that the mineral is classified in the subdivision “B. With only medium-sized cations ”is to be found, where the“ melanterite group ”with the system number is also found together with alpersite, boothite, mallardite, melanterite and zinc melanterite. 7.CB.35 forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns Bieberite to the class of "sulfates, chromates and molybdates" and there in the department of "water-containing acids and sulfates". Here it is also in the " melanterite group (heptahydrate, monoclinic: P 2 1 / c ) " with the system no. June 29, 2010 to be found in the subsection “Water-based acids and sulfates with AXO 4 × x (H 2 O)”.
Chemism
The theoretical composition of Bieberit Co [SO 4 ] · 7H 2 O consists of 20.96% cobalt (Co), 11.41% sulfur (S), 62.61% oxygen (O) and 5.02% hydrogen ( H). In natural Bieberit, however, a part of cobalt can by magnesium 1: (Mg) up to a ratio of Co: Mg = 2.8 replaces be.
Crystal structure
Bieberite crystallizes monoclinically in the space group P 2 1 / c (space group no. 14) with the lattice parameters a = 14.04 Å ; b = 6.50 Å; c = 10.92 Å and β = 105.3 ° and 4 formula units per unit cell .
properties
Bieberit dissolves completely in water and colors the solution pink-red. In the air and when heated to over 40.7 ° C, Bieberit changes into the hexahydrate Moorhouseit through dehydration .
Education and Locations
Bieberite is secondary to oxidation from cobalt-containing sulfides and arsenides . The accompanying minerals include erythrin , annabergite , pharmacolite , cobaltite and linneit .
As a rare mineral formation, Bieberite could only be detected at a few sites, with around 60 sites (as of 2018) being known. Because of its sensitivity to water, Bieberit is rarely found on heaps . In addition, it looks very similar in color to the erythrin that occurs in socialization. Many of the grades marked “Bieberite” in mineral collections were therefore found to be erythrin on closer analysis.
In addition to its type locality Bieber in Hesse, the mineral was also found in Germany in several mines in North Rhine-Westphalia such as the Wilder Mann mine near Müsen, the Eisenzecher Zug near Eiserfeld, the iron ore mine Storch & Schöneberg near Gosenbach, in the Maubacher Bleiberg ore mine in the district Düren, on the Mechernich Bleiberg and in the Kalenberg opencast mine near Mechernich , the Heidberg and Wildberg mines near Eckenhagen and the Reconciliation mine near Altenrath (Troisdorf) . Bieberit was also found in the Eupel mine near Niederhövels in Rhineland-Palatinate, on the Abrahamhalde at shaft 139 near Lauta and in the Schneeberg mine area in Saxony as well as in the Kamsdorf open-cast mine and on the Roten Berg in Thuringia.
In Austria, the mineral is known from some slag discovery sites near Kolm-Saigurn in the area of Alteck and Hoher Sonnblick ( Goldberg group ) as well as from today's Leogang show mine in the Leogang district of Schwarzleo in Salzburg and from an overburden dump in the Teichen pit (Langteichengraben) near the municipality of Kalwang in of Styria.
The only known location in Switzerland is a pegmatite - outcrop in the Valle del Molino at Claro TI in the canton of Ticino.
Other locations are in Chile, the Democratic Republic of the Congo, France, Greece, Italy, Japan, Portugal, Russia, Zimbabwe, Slovakia, Spain, the Czech Republic and the United States of America.
See also
literature
- JH Kopp: About the cobalt vitriol breaking into Bieber in Hanauischen and the arsenic oxide accompanying it . In: Carl Caesar Leonhard (Hrsg.): Pocket book for the entire mineralogy . 1st year. Johann Christian Hermann, Frankfurt am Main 1807, p. 104–119 ( available online at archive.org - Internet Archive ).
- JH Kopp: Chemical investigation of two new minerals from Bieber in Hanau. a. Cobalt vitriol . In: Adolph Ferdinand Gehlen (Ed.): Journal for chemistry, physics and mineralogy . tape 6 . Verlag der Realschulbuchhandlung, Berlin 1808, p. 157 ( limited preview in Google Book Search [accessed April 7, 2018]).
- Thomas Kellersohn, Robert G. Delaplane, Ivar Olovsson: Disorder of a trigonally planar coordinated water molecule in cobalt sulfate heptahydrate, CoSO 4 · 7D 2 O (bieberite) . In: Journal for Nature Research . 46B, June 4, 1991, pp. 1635-1640 , doi : 10.1515 / znb-1991-1209 ( semanticscholar.org [PDF; 5.2 MB ; accessed on April 8, 2018]).
- I-Ming Chou, Robert Seal II: Acquisition and Evaluation of Thermodynamic Data for Bieberite-Moorhouseite Equilibria at 0.1 MPa . In: American Mineralogist . tape 90 , 2005, pp. 912-917 ( unl.edu ).
- Günther J. Redhammer, Lisa Koll, Manfred Bernroider, Gerold Tippelt, Georg Amthauer, Georg Roth: Co 2+ -Cu 2+ substitution in bieberite solid-solution series, (Co 1-x Cu x ) SO 4 · 7H 2 O, 0.00 ≤ x ≤ 0.46: Synthesis, single-crystal structure analysis, and optical spectroscopy . In: American Mineralogist . tape 92 , 2007, p. 532–545 ( rruff.info [PDF; 780 kB ; accessed on April 8, 2018]).
Web links
- Mineral Atlas: Bieberite (Wiki)
- RRUFF Database-of-Raman-spectroscopy - Bieberite (English)
- American-Mineralogist-Crystal-Structure-Database - Bieberite (English)
Individual evidence
- ↑ 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 .
- ↑ a b c RJ Meyer: Cobalt (Co. Part A1. Element) . In: German Chemical Society (Hrsg.): Gmelins Handbuch der inorganic Chemie . 8th, completely revised edition. Springer, Berlin, Heidelberg 1969, ISBN 978-3-662-11856-6 , pp. 32–33 ( limited preview in Google Book Search - first edition: 1932).
- ↑ a b JH Kopp: About the cobalt vitriol breaking into Bieber in Hanauischen and the arsenic oxide accompanying it . In: Carl Caesar Leonhard (Hrsg.): Pocket book for the entire mineralogy . 1st year. Johann Christian Hermann, Frankfurt am Main 1807, p. 104–105 ( available online at archive.org - Internet Archive ).
- ↑ a b c d e 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. 384 .
- ↑ a b c Webmineral - Bieberite (English)
- ↑ a b c d Bieberite . 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; 65 kB ; accessed on April 6, 2018]).
- ↑ a b c d e Mindat - Bieberite (English)
- ↑ JH Kopp: About the cobalt vitriol breaking into Bieber in Hanauischen and the arsenic oxide accompanying it . In: Carl Caesar Leonhard (Hrsg.): Pocket book for the entire mineralogy . 1st year. Johann Christian Hermann, Frankfurt am Main 1807, p. 107 ( available online at archive.org - Internet Archive ).
- ^ JH Kopp: Chemical investigation of two new minerals from Bieber in Hanauischen. a. Cobalt vitriol . In: Adolph Ferdinand Gehlen (Ed.): Journal for chemistry, physics and mineralogy . tape 6 . Verlag der Realschulbuchhandlung, Berlin 1808, p. 162 ( limited preview in Google Book Search [accessed April 7, 2018]).
- ↑ JH Kopp: Chemical investigation of two new minerals from Bieber in Hanauischen. a. Cobalt vitriol . In: Adolph Ferdinand Gehlen (Ed.): Journal for chemistry, physics and mineralogy . tape 6 . Verlag der Realschulbuchhandlung, Berlin 1808, p. 158 ( limited preview in Google Book Search [accessed April 7, 2018]).
- ^ Wilhelm von Haidinger : First class: Akrogenide. IV. Order. Salts. VII. Vitriol salt. Bieberit . In: Handbook of determining mineralogy . Braumüller and Seidel, Vienna 1845, p. 489 (No. 16) ( rruff.info [PDF; 324 kB ; accessed on April 7, 2018]).
- ↑ Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason , Abraham Rosenzweig: Dana's New Mineralogy . 8th edition. John Wiley & Sons, New York (et al.) 1997, ISBN 0-471-19310-0 , pp. 612 .
- ↑ Joachim Lorenz: The historical mining on the hydrothermal Co-Ni-Bi veins, the copper shale of the Zechstein and the carbonate to oxidic Fe-Mn mineralization of Bieber in the Spessart. In: spessartit.de. Retrieved April 9, 2018 .
- ↑ Find location list for Bieberite at the Mineralienatlas and at Mindat