Argyrodite
| Argyrodite | ||
|---|---|---|
Specific gravity 6.2-6.5 | | |
| Optical properties | Weakly anisotropic | |
| Pleochroism | Weak | |
| References | [2][3] | |
Argyrodite is an uncommon silver germanium sulfide mineral with formula Ag8GeS6. The color is iron-black with a purplish tinge, and the luster metallic.
Discovered and named by Albin Weisbach in 1886,
The Freiberg mineral had previously been imperfectly described by August Breithaupt under the name "Plusinglanz", and Bolivian crystals were incorrectly described in 1849 as crystallized brongniardite.[5]
Isomorphous with argyrodite is the corresponding
, with composition (Cu4.7Ag3.3)GeS6.Argyrodite gets its name from the Greek words that loosely translate into "rich in silver".[2]
Argyrodite-type material
The term argyrodite is also used for other materials with a similar crystal structure, in particular lithium based argyrodite-type materials, which have received interest from researchers as a potential solid-state electrolyte for lithium-ion batteries.[6][7]
They are considered to be of the form:
Li
7-xBCh
6-xX
x
With x between 0 and 1, B denoting either phosphor or arsenic, Ch for sulfur or selenium and X for chlorine, bromine or iodine.[6] However, other forms exist and can be grouped into three main categories, halogen-based argyrodites, halogen-based argyrodites doped with additional semi-metal or metal components and halogen-free argyrodites based on Li, P, S along with a semi-metal.[8]
References
- S2CID 235729616.
- ^ a b Handbook of Mineralogy
- ^ a b Mindat.org
- ^ Weisbach, Albin (1886). "Argyrodit, ein neues Silbererz". Neues Jahrbuch für Geologie und Paläontologie. 2: 67.
- ^ a b Spencer 1911, p. 488.
- ^ ISBN 978-1-000-35180-4.
- PMID 32565618.
- ISSN 1793-6047.
Attribution:
- This article incorporates text from a publication now in the public domain: Spencer, Leonard James (1911). "Argyrodite". In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 2 (11th ed.). Cambridge University Press. p. 488.
