Mineralpedia Details for Acanthite
Acanthite
Named after the Greek word acanthi, meaning “thorn,” in reference to the mineral’s common crystal habit. Acanthite is a common mineral that occurs in medium- to low-temperature hydrothermal sulfide veins and in secondary enrichment zones. It can be found in association with silver, pyrargyrite, proustite, polybasite, stephanite, aguilarite, galena, chalcopyrite, sphalerite, calcite, and quartz. A widespread mineral, but fine crystals can be found in localities in the Czech Republic, Germany, Mexico, the United States, Canada, and Chile. Found in silver rich deposits as lead grey to black tarnished, soft, metallic pseudocubic crystals or elongatic prismatic crystals with rounded corners commonly associated with Silver. Sectile and easily cut by a knife.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/acanthite.pdf
- Formula
- Ag2S
- Crystal System
- Monoclinic
- Crystal Habit
- Blocky, Skeletal, Arborescent
- Cleavage
- poor to none
- Luster
- Metallic
- Color
- lead gray, gray, iron black
- Streak
- shining black
- Class
- Monoclinic - Prismatic
- Fracture
- Sectile
- Hardness
- 2-2.5
- WebMineral
- View Acanthite
- Mindat
- View Acanthite
Acanthite from Linqiu, Shanxi Province, China
1.3cm grey, cubic Acanthite crystal with Silver.
Acanthite from St. Andreasberg dist., Harz, Lower Saxony, Germany
- Special Info
- Antique Specimen
Old specimen with an inked label. This specimen is loaded with cubic, dull silvery Acanthite crystals throughout the brecciated matrix. The largest crystal is 5mm across with dozens smaller. Excellent older specimen from this classic locality.
Acanthite from Freiberg dist., Erzgebirge, Saxony, Germany
Numerous well-formed Acanthite crystals in singles and clusters from 2-3.5mm. This is simply a superb specimen not only for the region but also for its crystals.
