Acanthite
| ID | 442 | |
|---|---|---|
| Mineral | Acanthite | |
| Location | Snarum - Viken - Norway | |
| Fluorescence | LW-UV: close SW-UV: close |
|
| Mindat.org |
View Acanthite information at mindat.org |
|
Mindat data
| ID | 10 |
|---|---|
| Long ID | 1:1:10:5 |
| Formula |
Ag2S
|
| IMA Status |
0 1 |
| Other Occurrences | A common silver species in moderately low-temperature hydrothermal sulphide veins, and in zones of secondary enrichment. Widespread in silver deposits. Localities for fine primary and paramorphic crystals include Jáchymov (St Joachimsthal), Czech Republic [TL]; In Germany, at Freiberg, Schneeberg, Annaberg, and Marienberg, Saxony; and from St Andreasberg, Harz. In Mexico, large paramorphs from Arizpe, Sonora; In the Rayas and other mines at Guanajuato; And from many mines in Zacatecas, Chihuahua, etc; In the USA, at Butte, Silver Bow Co., Montana; Tonopah, Nye Co. and the Comstock Lode, Virginia City, Storey Co., Nevada; From various mines at Cobalt, Ontario, Canada; At Chañarcillo, south of Copiapó, Atacama, Chile. |
| Discovery Year | 1855 |
| Diapheny | Opaque |
| Tenacity | sectile |
| Colour | lead grey, black |
| Hardness (min) | 2.0 |
| Hardness (max) | 2.5 |
| Luminescence | None |
| Lustre | Metallic |
| About the name | Named in 1855 by Gustav Adolf Kenngott from the Greek άκανθα ("akantha") meaning "thorn", in allusion to the thorn-like crystal shape of his material. With the advent of instrumental analytical equipment, it was discovered that the mineral called "argentite" which had isometric crystal shapes has an atomic structure and chemistry identical to acanthite. |
| Streak | lead grey |
| Crystal System | Monoclinic |
| Cleavage Type | None Observed |
| Fracture type | Sub-Conchoidal |
| Morphology | Typically found as pseudo-cubic and pseudo-octahedral crystals, paramorphic after argentite. Also found as thorn-shaped monoclinic crystals, usually small to microscopic in size. Large primary crystals are uncommon, other than fine overgrowths and replacements of native silver; they are prismatic to long prismatic, elongated along [001], to 2.5 cm, may be tubular; also massive. |
| UV | Not fluorescent in UV |
| key_elements |
0 |
| shortcode_ima | Aca |
| Group | Acanthite Group |
Details
Price: € 50
Dimensions: Not registered
Weight: 774 g
Visibile in overview:
Notes:
| Symbol | Element | |
|---|---|---|
| Ag | Silver | |
| S | Sulfur |