Heinrichite
| Heinrichite | |
|---|---|
 |
|
| General and classification | |
| other names |
|
| chemical formula | Ba (UO 2 ) 2 (AsO 4 ) 2 · 10H 2 O |
|
Mineral class (and possibly department) |
Phosphates , arsenates and vanadates |
|
System no. to Strunz and to Dana |
8.EB.05 ( 8th edition : VII / D.20a) 40.02a.04.01 |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | monoclinic prismatic; 2 / m |
| Space group | P 2 / c (No. 13) |
| Lattice parameters |
a = 7.1548 Å ; b = 7.1340 Å; c = 21.290 Å β = 104.171 ° |
| Formula units | Z = 2 |
| Frequent crystal faces | {001}, {100}, {110} |
| Physical Properties | |
| Mohs hardness | 2.5 |
| Density (g / cm 3 ) | measured: not defined; calculated: 3.61 |
| Cleavage | completely after {001}, clearly after {100} |
| Break ; Tenacity | brittle |
| colour | yellow to yellow-green |
| Line color | light yellow, almost white |
| transparency | transparent to translucent |
| shine | Glass gloss to pearlescent gloss |
| radioactivity | medium alpha emitting |
| Crystal optics | |
| Refractive indices |
n ω = 1.605 n ε = 1.573 |
| Birefringence | δ = 0.032 |
| Optical character | uniaxial negative |
| Other properties | |
| Chemical behavior | toxic |
| Special features | fluorescent |
Heinrichite (also arsenouranocircite or uranosandbergite ) is a seldom occurring mineral from the mineral class of " phosphates , arsenates and vanadates " with the chemical composition Ba (UO 2 ) 2 (AsO 4 ) 2 · 10H 2 O and therefore chemically a water-containing barium - Uranyl arsenate.
Heinrichite crystallizes in the monoclinic crystal system and develops transparent to translucent crystals and leafy aggregates of yellow to yellow-green color and a glass-like to mother-of-pearl-like sheen on the surfaces. Heinrichit leaves a light yellow to almost white line on the marking board .
With a Mohs hardness of 2.5, Heinrichite is still one of the soft minerals and is slightly easier to scratch with a copper coin than the reference mineral calcite .
Etymology and history
Heinrichite was discovered in 1958 in the "White King Mine" in Lakeview (Lake County, Oregon , United States ). But as well as samples from the "pit Anton" in order to determine the mineral wittichener Heubachtal ( Baden-Wuerttemberg ) were used, and this place is considered type locality .
The mineral was first described in the year it was found by Eugene B. Gross, Alice S. Corey, Richard S. Mitchell and Kurt Walenta , who named it in honor of the US mineralogist and professor at the University of Michigan , Eberhardt William Heinrich (1918–1991 ), named after this.
The type material of the mineral is in the National Museum of Natural History in Washington, DC in the USA under the catalog no. 121950 kept.
classification
Already in the outdated 8th edition of the systematics of minerals according to Strunz , Heinrichit belonged to the class of "phosphates, arsenates and vanadates" and there to the division of "water-containing phosphates, arsenates and vanadates with foreign anions " (more precisely to the uranyl phosphate family , arsenates and -Vanadate ), where he together with autunite , Bassetit , Fritz Scheit , Kahlerit , Kirchheimerit , Natrouranospinit , Nováčekit , Sabugalit , Saléeit , Torbernit , Uramphit , Uranocircit , Uranospathit , Uranospinit and Zeunerit the "Uranit-series" with the system -No. VII / D.20a .
In the Lapis mineral directory according to Stefan Weiß, 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. VII / E.01-120 . In the "Lapis system" this corresponds to the section "Uranyl phosphates / arsenates and uranyl vanadates with [UO 2 ] 2+ - [PO 4 ] / [AsO 4 ] 3- and [UO 2 ] 2+ - [V 2 O 8 ] 6- , with isotypic vanadates (Sincosit-R.) “, Where Heinrichit together with Autunit, Fritzscheit, Kahlerit, Sodium Autunit , Nováčekit, Rauchit , Sabugalit, Saléeit, Torbernit, Trögerit , Uranocircit, Uranospinit, Zeunerit die "Autunit group" with the system no. VII / E.01 forms (as of 2018).
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 heinrichite under the category of "uranyl phosphates and arsenates". However, this is further subdivided according to the molar ratio of the uranyl complex (UO 2 ) to the phosphate, arsenate or vanadate complex (RO 4 ), so that the mineral according to its composition in the sub-section "UO 2 : RO 4 = 1: 1 "Is to be found, where together with Autunit, Kahlerite, Kirchheimerite, Metarauchit , Nováčekit-I, Nováčekit-II, Saléeit, Torbernit, Uranocircit-I, Uranocircit-II, Uranospinit, Xiangjiangit and Zeunerit the" Autunit group "with the system No. 8.EB.05 forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns heinrichite to the class of "phosphates, arsenates, vanadates" and there in the section "water-containing phosphates, etc.". Here it is only together with metaheinrichite in the unnamed group 40.02a.04 within the subsection “ Water-containing phosphates etc., with the general composition A 2+ (B 2+ ) 2 (XO 4 ) · x (H 2 O) (UO 2 ) 2+ ”.
Crystal structure
Heinrichite crystallizes monoclinically in the space group P 2 / c (space group no. 13) with the lattice parameters a = 7.1548 Å ; b = 7.1340 Å; c = 21.290 Å and β = 104.171 ° as well as two formula units per unit cell .
properties
Due to the elements barium , arsenic and uranium contained in the compound, heinrichite is highly toxic, radioactive and carcinogenic . The specific activity is about 73.88 k Bq / g (for comparison: natural potassium 31.2 Bq / g).
The mineral fluoresces under long-wave and short-wave UV light in a strong green to greenish-yellow color.
Heinrichite dehydrates very quickly to metaheinrichite in the air .
Education and Locations
Heinrichite forms as a secondary mineral in the oxidation zone of uranium deposits . In addition to metaheinrichite, accompanying minerals are arseniosiderite , erythrin , nováčekite, pitticit , uraninite and zeunerite.
So far (as of 2010) the mineral has been found at around 20 sites around the world: near Kruth , Ébreuil , Lodève and Guéret in France; Baden-Württemberg , Bavaria , Rhineland-Palatinate and Saxony in Germany; in the Greek Attica ; in Catalonia, Spain and, in addition to its Oregon type, in Utah in the USA.
Precautions
Since the mineral is highly toxic, radioactive and carcinogenic, in particular the two substances arsenic and uranium accumulate in the body if they are absorbed, direct contact with the mineral must be avoided at all costs and the affected skin areas must be washed thoroughly after contact.
See also
literature
- Eugene B. Gross, Alice S. Corey, Richard S. Mitchell, Kurt Walenta : Heinrichite and metaheinrichite, hydrated barium uranyl arsenate minerals . In: American Mineralogist . tape 43 , 1958, pp. 1134–1143 (English, rruff.info [PDF; 588 kB ; accessed on October 13, 2019]).
- Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 655 (first edition: 1891).
Web links
- Mineral Atlas: Heinrichit (Wiki)
- American-Mineralogist-Crystal-Structure-Database - Heinrichite. In: rruff.geo.arizona.edu. Retrieved October 13, 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: September 2019. (PDF 2672 kB) In: cnmnc.main.jp. IMA / CNMNC, Marco Pasero, September 2019, accessed October 13, 2019 .
- ^ A b David Barthelmy: Heinrichite Mineral Data. In: webmineral.com. Retrieved October 13, 2019 .
- ↑ a b c Andrew J. Locock, Peter C. Burns, Theodore M. Flynn: Structures of strontium- and barium-dominant compounds that contain the autunite-type sheet . In: The Canadian Mineralogist . tape 43 , 2005, p. 721–733 (English, rruff.info [PDF; 432 kB ; accessed on October 13, 2019]).
- ↑ a b c Heinrichite . 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; 66 kB ; accessed on October 13, 2019]).
- ↑ a b Heinrichite. In: mindat.org. Hudson Institute of Mineralogy, accessed October 13, 2019 .
- ↑ Catalog of Type Mineral Specimens - H. (PDF 81 kB) In: docs.wixstatic.com. Commission on Museums (IMA), December 12, 2018, accessed August 29, 2019 .
- ↑ 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 .
- ↑ Ernest H. Nickel, Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF 1703 kB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed October 13, 2019 .
- ↑ Find location list for Heinrichit in the Mineralienatlas and Mindat , accessed on October 13, 2019.