Chabazite
| Chabazite | |
|---|---|
 |
|
| General and classification | |
| chemical formula | see single minerals |
|
Mineral class (and possibly department) |
Silicates and germanates - tectosilicates (tectosilicates); Zeolite group - cube zeolites |
|
System no. to Strunz and to Dana |
9.GD.10 ( 8th edition : VIII / J.26) 77.01.02.01 to 77.01.02.01c |
| Crystallographic Data | |
| Crystal system | trigonal |
| Crystal class ; symbol | ditrigonal-scalenohedral; 3 2 / m |
| Space group | R 3 m (No. 166) |
| Lattice parameters | see crystal structure |
| Formula units | Z = 6 Please complete the source as an individual reference |
| Frequent crystal faces | {10 1 1}, {01 1 2}, {02 2 1}, {21 3 1}, {21 3 4} |
| Twinning | often complementary and penetrating twins according to {0001} |
| Physical Properties | |
| Mohs hardness | 4 to 5 |
| Density (g / cm 3 ) | measured: 2.05 to 2.20; calculated: 2.035 |
| Cleavage | indistinct to distinct after {10 1 1} |
| Break ; Tenacity | uneven to scalloped |
| colour | colorless to white, less often yellowish, pink to reddish, greenish |
| Line color | White |
| transparency | transparent to translucent |
| shine | Glass gloss |
| Crystal optics | |
| Refractive indices |
n ω = 1.480 to 1.485 n ε = 1.478 to 1.490 |
| Birefringence | δ = 0.005 to 0.008 |
| Optical character | uniaxial positive |
Chabazite is the collective name for an unspecified mineral of a mixed crystal series with the end members Chabazite-Ca , Chabazite-K , Chabazite-Mg , Chabazite-Na (also Herschelite ) and Chabazite-Sr from the mineral class recognized by the International Mineralogical Association (IMA) the "Silicates and Germanates". Structurally, the Chabazites belong to the framework silicates (tectosilicates) and there to the family of zeolites .
All members of the Chabazite series crystallize in the trigonal crystal system with the following chemical composition :
- Chabazite-Ca - Ca 2 [Al 4 Si 8 O 24 ] · 13H 2 O
- Chabazite-K - (K 2 NaCa 0.5 ) [Al 4 Si 8 O 24 ] · 11H 2 O
- Chabazite Mg - (Mg 0.7 K 0.5 Ca 0.5 Na 0.1 ) [Al 3 Si 9 O 24 ] · 10H 2 O
- Chabazite Na - (Na 3 K) [Al 4 Si 8 O 24 ] • 11H 2 O
- Chabazite-Sr - (Sr, Ca) 2 [Al 4 Si 8 O 24 ] · 11H 2 O
Chabazite is therefore a water-containing aluminosilicate with varying levels of calcium , potassium , magnesium , sodium and strontium .
Chabazite usually develops rhombohedral and pseudocubic, cube-like crystals and cross twins , but also occurs in the form of granular or massive mineral aggregates . In its pure form, that is to say without any additives outside the formula, chabazite is colorless and transparent or appears white due to multiple refraction due to lattice defects or polycrystalline formation. Through the addition of iron (Fe), for example , the mineral can occasionally take on a yellow-orange, pink or reddish to brownish color, with the transparency decreasing accordingly. Greenish chabazites are also very rarely found.
Etymology and history
The zeolite mineral was first described in 1777 by Ignaz von Born , who called it Zeolithus crystallisatus cubicus Islandiae . In 1783 Jean-Baptiste Romé de L'Isle shortened this name to Zéolite en cube .
Louis-Augustin Bosc d'Antic coined for this "Würfelzeolith" 1892 the proper name "Chabazie" after the ancient Greek word for Hagelstein (see also as in medicine hailstone known eyelid inflammation chalazion ), since the mineral usually smaller in form of white crystals was found. The original ancient Greek spelling of the word, however, was Χαλάζιος [chalazios]. The word became known through the Greek didactic poem " Lithika " from the 4th century AD, where it was used in the special vocative form Χαλάζιε in the poem line:
“I also considered trying you, divine Chalazios, and found your excellent strength. You can do both, cool a heated illness and help me when I'm stung by the scorpion. "
In the 18th century, however, the word spread in the misspelling Χαβάζιε, which was retained by the mineralogists despite the correction made in 1781 by Thomas Tyrwhitt (1730–1786). René-Just Haüy changed Bosc d'Antic's chosen name to Chabasie in 1801 and Abraham Gottlob Werner finally coined the German name Chabazit. The synonym Chabasin has also been passed down through Dietrich Ludwig Gustav Karsten , although this was not generally accepted.
In the course of the reorganization of the zeolite family in 1997, the end members of the heulandite mixed series were redefined and the predominant cations in the formula were appended as abbreviations.
The type locality for the individual minerals applies to
- Chabasit-Ca the place Colle del Lares in the Nicolò valley, a side valley of the Fassa valley in the Italian province of Trentino (South Tyrol)
- Chabasit-K the town of Ercolano near the Monte Somma volcano, which belongs to the Vesuvius complex, in the Italian metropolitan city of Naples
- Chabazite-Mg from the Karikás quarry near the municipality of Bazsi in the Hungarian county of Veszprém
- Chabasit-Na the place Aci Trezza or the municipality Aci Castello near the Etna volcanic complex in the Italian metropolitan city of Catania in Sicily
- Chabazite Sr mountain Suoluaiw (Суолуайв) near the village of Lovozero in Russia's Murmansk Oblast
classification
Already in the outdated but still partially in use 8th edition of the mineral classification by Strunz the chabazites belonged to the mineral class of "silicates and Germanates" and then to the Department of "framework silicates (tectosilicates), with zeolites" where they together with Bellbergit , erionite Ca , Erionit-K , Erionit-Na , Gmelinit-Ca , Gmelinit-K , Gmelinit-Na , Lévyn-Ca , Lévyn-Na , Mazzit-Mg , Mazzit-Na , Offretit , Perlialite , Tschernichit and Willhendersonite within the zeolite group the subgroup the "Cube Zeolite I" with the system no. VIII / J.26 .
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 the Chabazites to the category of “tectosilicates with zeolitic H 2 O; Family of zeolites ”. This is, however, further subdivided according to the structure of the framework, so that the minerals can be found in the sub-section "Chains of five rings" according to their composition, where they only together with Willhendersonite form the "Chabazite group" with system no. Form 9.GD.10 .
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the Chabazite to the class of "silicates and Germanates" and there in the department of "structural silicates: zeolite group". Here they are in the group " Chabazite and allied species " with the system no. 77.01.02 to be found in the subsection "Real Zeolites".
Crystal structure
All Chabazites crystallize trigonal in the space group R 3 m (space group no. 166) with the following lattice parameters with 6 formula units per unit cell
- Chabazite-Ca: a = 13.80 Å and c = 15.02 Å
- Chabazite-K: a = 13.849 Å and c = 15.165 Å
- Chabazite Mg: a = 13.777 Å and c = 14.872 Å
- Chabazite Na: a = 13.863 Å and c = 15.165 Å
- Chabazite Sr: a = 13.715 Å and c = 15.09 Å
Aluminosilicate framework
The Si 4+ and Al 3+ ions are tetrahedrally surrounded by four oxygen anions, so that the cations are in the center and the anions at the corners of the coordination polyhedron .
The (Al, Si) O 4 tetrahedra are linked at all four corners via shared oxygen ions to form a framework that has a negative (anionic) charge due to the incorporation of Al instead of Si. This is compensated for by the installation of cations in the cavities of the framework.
The Chabazite framework (framework type "CHA") is made up of rings of 8, 6 and 4 and is characterized by a three-dimensional channel system. It is traversed in three spatial directions by channels that allow the passage of particles with a maximum diameter of 3.72 Å. The cavities in the framework can accommodate particles with a maximum diameter of 7.37 Å. The proportion of the accessible volume is 17.3% and the framework density is 15.1 tetrahedra / 1000 Å 3 .
- Secondary building units
The CHA framework can be constructed from any of the following secondary building units : 6 (flat 6-rings), 6-6 (double 6-rings), 4 (4-rings) or 4-4 (double 4-rings) .
The CHA framework belongs to the ABC-6 family. The two-dimensional periodic structural unit (PerBU) consists of a hexagonal arrangement of not directly linked, flat 6-ring rings in the ab plane. These levels with rings of 6 are stacked on top of each other in the c-direction, each with an offset of + (2 / 3a + 1 / 3b), - (2 / 3a + 1 / 3b) or + (0a + 0b - no offset) . The 6-rings isolated within a layer are connected via 4-rings with the 6-rings of adjacent layers to form a framework, so that an AA-BB-CC sequence of the periodic structural unit results for the CHA framework.
- Building units
An alternative description builds the scaffolding structure from larger building units, the composite building units . The CHA framework can be described with double rings of 6 (d6r) or with the chabazite cavern (cha). The chabazite cavern is the pore space of the chabazite and is delimited by twelve rings of 4, two rings of 6 and six rings of 8 (area symbol [4 12 .6 2 .8 6 ]) and can contain particles with a maximum diameter of 7, Record 37 Å in diameter. The cha caverns are connected in the direction of the a-axis via the 6-ring and in the direction of the spatial diagonals [111] via the 8-ring. This connection of the cha caverns via the large rings of 8 results in the three-dimensional channel system of the CHA framework, through which particles with a diameter of up to 3.72 Å can be exchanged. The “pore descriptor” of the CHA framework is thus {3 [4 12 .6 2 .8 6 ] <100> (6-ring), <111> (8-ring)}.
Education and Locations
Chabazites are mainly formed hydrothermally in bubble cavities ( miaroles ) of igneous rocks such as granitic pegmatites , basalts and phonolites , but often also occur at the outlet openings of thermal springs . In addition to other zeolites such as stilbite , harmotome , calcite , dolomite , epidote , melilite , nepheline and tridymite as well as various amphiboles and pyroxenes , axinites and olivines can occur as accompanying minerals .
As frequent mineral formations, Chabazites can generally be found at many sites, with a total of over 1700 sites known to date (as of 2014). However, since these finds are rarely analyzed with sufficient precision, information on the individual English members with regard to the number of sites is accordingly inaccurate.
The Faroe Islands belonging to Denmark , where colorless and white crystal twins (penetrating twins) of up to 6 centimeters in size have been discovered, are known due to extraordinary chabazite finds .
In Germany chabazites one found so far among other things, in an amphibolite - quarry on Urenkopf at Haslach in the quarries Michel Berg am Katzenbuckel and Höwenegg at Immendingen and at several locations in the Kaiserstuhl in Baden-Wuerttemberg; in some places in the Fichtel Mountains and in many places in the Bavarian Forest in Bavaria; in various places in the Dillkreis , in the district of Gießen , in the Odenwald and on the Vogelsberg in Hesse; near Bad Harzburg , Braunlage and Sankt Andreasberg in Lower Saxony; near Königswinter in the North Rhine-Westphalian Siebengebirge; in many places in the Eifel (Daun, Ettringen, Kelberg, Niederzissen), in the Hunsrück (Idar-Oberstein, Niederwörresbach) and in the Westerwald (Bad Marienberg, Linz on the Rhine) in Rhineland-Palatinate; in the Becker quarry ( Hellerberg ) near Freisen in Saarland; in some places in the Saxon Ore Mountains ; near Groß Pampau in Schleswig-Holstein and near Unterbreizbach and Weitisberga in Thuringia.
In Austria, the mineral has so far been found mainly in the Hohe Tauern from Carinthia to Salzburg and the Koralpe from Carinthia to Styria. It also came to light in a basalt quarry on Pauliberg in Burgenland and on Zamser Grund (Pfitscherpass) in Tyrol.
In Switzerland, chabazite is known from the Grimsel Pass and the Oberaarsee in the canton of Bern; from several locations in the Bregagliatal and the Vorderrheintal in the canton of Graubünden as well as from various sites in the cantons of Ticino , Uri and Valais .
Other locations include Argentina, Australia, Belgium, Brazil, Bulgaria, Chile, China, Costa Rica, Denmark, Finland, France and the French overseas departments Mayotte and Réunion, Greece, Greenland, India, Indonesia, Ireland, Iceland, Israel, Italy, Japan, Yemen, Jordan, Canada, Kazakhstan, Kenya, Korea, Madagascar, Morocco, Mexico, Myanmar ( Burma ), Namibia, New Zealand, Nicaragua, Norway, Panama, Poland, Portugal, Romania, Russia, Sweden, Slovakia , Spain, South Africa, Taiwan, Tanzania, the Czech Republic, Ukraine, Hungary, Venezuela, the United Kingdom (UK), the United States of America (USA) and Cyprus.
Chabazite-Ca could be detected in rock samples from the Mid-Atlantic Ridge (hydrothermal field Logatchev-1).
use
As true zeolites, chabazites are also suitable as ion exchangers , molecular sieves and for many other technical applications due to their microporous lattice structure , but are now often produced synthetically, see also possible uses of zeolites .
See also
literature
- L. Bosc D'Antic: Mémoire sur la chabazie. In: Journal d'Histoire Naturelle. Volume 2 (1792), pp. 181-184 ( PDF 2.55 MB )
- Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke , Stuttgart 1978, ISBN 3-432-82986-8 , pp. 796–797 (first edition: 1891).
- Douglas S. Coombs, Alberto Alberti, Thomas Armbruster, Gilberto Artioli, Carmine Colella, Ermanno Galli, Joel D. Grice, Friedrich Liebau, Joseph A. Mandarino, Hideo Minato, Ernest Henry Nickel , Elio Passengeria, Donald R. Peacor, Simona Quartieri , Romano Rinaldi, Malcom Ross, Richard A. Sheppard, Ekkehart Tillmanns, Giovanna Vezzalini: Recommended nomenclature for zeolite minerals: report of the Subcommittee on Zeolites of the International Mineralogical Association, Commission on New Minerals and Mineral Names. In: The Canadian Mineralogist. Volume 35 (1997), pp. 1571–1606 ( PDF 3.3 MB ; Heulandit series from p. 9)
- Martin Okrusch, Siegfried Matthes: Mineralogy. An introduction to special mineralogy, petrology and geology . 7th fully revised and updated edition. Springer Verlag, Berlin et al. 2005, ISBN 3-540-23812-3 , pp. 128 (Chabazite-Ca) .
Web links
- Mineral Atlas: Chabazite Series or Mineral Atlas: Chabazite-Ca , Chabazite-K , Chabazite-Mg , Chabazite-Na and Chabazite-Sr (Wiki)
- Mindat - Chabazite or Chabazite-Ca , Chabazite-K , Chabazite-Mg , Chabazite-Na and Chabazite-Sr (English)
- Webmineral - Chabazite-Ca , Chabazite-K , Chabazite-Na and Chabazite-Sr (English)
- Mineral Lexicon - Chabazite
- Database-of-Raman-spectroscopy - Chabazite
Individual evidence
- ^ 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. 918 .
- ↑ Chabazite-Ca , In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America , 2001 ( PDF 79.8 kB )
- ^ Ulrich Henn, Claudio C. Milisenda: Gemmological Tables . German Gemmological Association, 2004, ISBN 3-932515-44-7 , p. 2 ( gemdat.org ).
- ↑ 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. 614 .
- ↑ Stefan Weiß: The large Lapis mineral directory. All minerals from A - Z and their properties . 5th completely revised and supplemented edition. Weise, Munich 2008, ISBN 978-3-921656-70-9 .
- ↑ a b c d e IMA / CNMNC List of Mineral Names; March 2014 (PDF 1.53 MB)
- ↑ Gemmology.ch - Chabazite ou (Adipite, Acadialite) series (French)
- ↑ 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. 195 .
- ↑ a b Ch. Baerlocher, LB McCusker: Database of Zeolite Structures - Framework Type CHA
- ↑ a b Ch. Baerlocher, LB McCusker: Database of Zeolite Structures - Building scheme for CHA (PDF 258 kB) and Henk van Koningsveld: Schemes for Building Zeolite Framework Models (PDF 2.32 MB)
- ↑ Mindat - Number of localities for Chabazite
- ↑ Petr Korbel, Milan Novák: Mineral Encyclopedia . Nebel Verlag GmbH, Eggolsheim 2002, ISBN 3-89555-076-0 , p. 279 ( Dörfler Natur ).
- ↑ List of localities for Chabazite at the Mineralienatlas and at Mindat
- ↑ Mindat - Logatchev-1 hydrothermal field, Mid-Atlantic Ridge complex, Atlantic Ocean