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.
Acanthite from Jachymov, Erzgegirge, Bohemia, Czech Republic
A small specimen with two very nice crystals of Acantite, the largest to 5mm. Classic locality.
Acanthite from Cobalt-Gowganda dist., Ontario, Canada
- Special Info
- EDS Confirmed
A 5mm cube of Acanthite in matrix with some Silver. There are several other smaller crystals of Acanthite not shown.
Acanthite from Burro Mountains dist., Grant Co., New Mexico, United States
A layer of compact dull silver Acanthite, presumably crystallized in thin fracture of carbonate rock.
Acanthite from Schneeberg dist., Erzgebirge, Saxony, Germany
1-4mm steely grey Acanthite crystals in abundance with good Calcite crystals.
Acanthite on Silver from O'Brien mine, Cobalt, Ontario, Canada
- Special Info
- Antique Specimen
The specimen is mostly a solid leaf of Silver with a coating of Acanthite. This has good provenance with an old inked label stuck on the specimen and dated 1980. With it is a nice large label from the "Department of Mines Geological Survey" of Canada with a number matching the specimen (7720).
Acanthite from Mexican mine, Comstock Lode, Storey Co., Nevada, United States
Really not much of a specimen as far as silver goes. But the specimen shows pervasive Silver crystal grains throughout the specimen with other sulfides, namely Acanthite. Both are in 1mm and less grains throughout the grey mass with a Quartz vein. The stuck on label gives good provenance, and any serious Nevada or mining history collector should have this in their collection.
Acanthite from Fresnillo, Zacatacas, Mexico
Cubes of Acanthite from 1-3mm all over matrix.
Acanthite from San Juan de Rayas mine, Guanajuato, Mexico
Crude cubic silvery grey Acanthite crystals to 2mm. The entire specimen is Acanthite, soft and sectile.
Choice hoppered habit Acanthite crystals large crystal group measuring 2cm.
Acanthite from Keeley-Frontier mine, Cobalt dist., Ontario, Canada
Soft, sectile mass of Acanthite with many crude forms of cubic crystals. The cluster at the tip is 7mm across. The specimen comes from the historic cobalt/silver Keeley-Frontier mine located in one of the largest silver mining districts in the world. The mine produced an incredible 3.3 million pounds of cobalt and 19.1 million ounce of silver. There is associated Calcite in mass and as crystals, a clear indication that the specimen was never etched.
Acanthite from Guanajuato, Guanajuato, Mexico
Excellnet thumbnail of Acanthite with superb cubic crystals to 2.5mm.
Acanthite from Batopilas, Chihuahua, Mexico
An old-timer of Acanthite with Silver. The Acanthite measures 7mm. The Silver is all over the specimen, but the best are two wires to 1-2mm around the Acanthite. Acanthite of this size are generally not seen from Batopilas.
Acanthite from Bulldog mine, Creede dist., Mineral Co., Colorado, United States
Large slab of Acanthite and native Silver concentrically banded along tips of Quartz crystals.
Acanthite from Niccola Secci mine, Sarrabus, Sardinia, Italy
- Special Info
- Antique Specimen
Oldie from a little known locality in Sardinia with an old Wards label. The Acanthite is to 8mm and has a little vial with a few grains.
