Theuerdankite, Ag3AsO4, a new mineral from the Alter Theuerdank Mine, St. Andreasberg, Germany

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00023272%3A_____%2F24%3A10136529" target="_blank" >RIV/00023272:_____/24:10136529 - isvavai.cz</a>

Alternative codes found

RIV/68378271:_____/24:00602533

Result on the web

<a href="https://www.cambridge.org/core/journals/mineralogical-magazine/article/theuerdankite-ag3aso4-a-new-mineral-from-the-alter-theuerdank-mine-st-andreasberg-germany/749901CDE123C70965ACFBF230204963" target="_blank" >https://www.cambridge.org/core/journals/mineralogical-magazine/article/theuerdankite-ag3aso4-a-new-mineral-from-the-alter-theuerdank-mine-st-andreasberg-germany/749901CDE123C70965ACFBF230204963</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1180/mgm.2024.44" target="_blank" >10.1180/mgm.2024.44</a>

Result language

angličtina

Original language name

Theuerdankite, Ag3AsO4, a new mineral from the Alter Theuerdank Mine, St. Andreasberg, Germany

Original language description

The new mineral theuerdankite, ideally Ag3AsO4, was found in the Alter Theuerdank Mine, Beerberg, St. Andreasberg, Goslar District, Lower Saxony, Germany. Theuerdankite occurs as aggregates of anhedral grains up to 3 mm in size, growing in cavities of strongly supergene-weathered material consisting of native silver and chlorargyrite (but with calcite present). It is dark violet, changing to reddish and black when exposed to the air and light. It has a grey to violet grey streak; when readily fresh, its streak is brownish-red. The Mohs hardness is about 2. It is brittle without any observable cleavage or parting and with a conchoidal fracture. The calculated density is 6.622 g.cm-3. In reflected light, theuerdankite is dark grey with a pinkish tint, without any observable bireflectance, pleochroism, or anisotropy. It shows dark red internal reflections. The reflectance values for wavelengths recommended by the Commission on Ore Mineralogy of the IMA are (R %): 13.3 (470 nm), 12.8 (546 nm), 12.7 (589 nm), 12.5 (650 nm). The empirical formula (based on 4 apfu) are Ag3.00As1.00O4. Theuerdankite is cubic, space group P-43n, a = 6.144(2) Å, V = 231.93(13) Å3 and Z = 2. The six strongest X-ray powder diffraction lines are [dobs in Å, (I), hkl]: 3.0736, (22), 200; 2.7502, (100), 210; 2.5106, (55), 211; 1.7050, (36), 320; 1.6249, (44), 321; 1.3412, (17), 421. The crystal structure of theuerdankite (R1 = 1.69% for 519 reflections having I &gt; 3σ(I)), is isotypic to those of synthetic Ag3AsO4 and Ag3PO4. The Gram-Charlier development describing the higher-order tensors representing the atomic displacement parameters of the silver atom was implemented, documenting that silver tends to behave in the theuerdankite structure anharmonically at room temperature.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10504 - Mineralogy

Project

<a href="/en/project/EH22_008%2F0004594" target="_blank" >EH22_008/0004594: Teraferroics for ultra-high capacity, speed and energy-efficiency of information technology</a><br>

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2024

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Mineralogical Magazine

ISSN

0026-461X

e-ISSN

—

Volume of the periodical

88

Issue of the periodical within the volume

5

Country of publishing house

GB - UNITED KINGDOM

Number of pages

8

Pages from-to

557-564

UT code for WoS article

001348173000001

EID of the result in the Scopus database

—