Mineralpedia Details for Arsenopyrite
Name is a combination of the old term “arsenical pyrites.” Silver white to steel grey, often tarnish giving an iridescence. Crystals short prismatic, often elongated parallel to c-axis. Uncommonly twinned as star-like trillings. Usually granular to massive. Arsenopyrite is the most abundant and widespread of the arsenic minerals and has thousands of worldwide localities, some of which have large and/or fine crystals and include Germany, Serbia, Portugal, Sweden, Greece, England, the United States, Mexico, Canada, Japan, and many others. Most commonly found in medium to high temperature veins. Common in metamorphic deposits, sparse in pegmatites.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/arsenopyrite.pdf
- Crystal System
- Crystal Habit
- Striated, Euhedral Crystals, Prismatic
- one distinct
- tin white, light steel gray
- Geological Setting
- Widespread. Most commonly found in medium to high temperature veins.
- Monoclinic - Prismatic
- 5.5 to 6
- View Arsenopyrite
- View Arsenopyrite
Arsenopyrite from Double Rainbow mine, Galena, Lawrence Co., South Dakota, United States
8mm replacements of Pyrrhotite.
Arsenopyrite from Panasqueira, Covilha, Castelo Branco dist., Portugal
Large crystal clusters of highly reflective Arsenopyrite with crystals to over 5cm.
Arsenopyrite from Hedley, Osoyoos Mining Division, British Columbia, Canada
Granular or massive steel grey or tin white Arsenopyrite from 5 to 10mm.
Arsenopyrite from Obira mine, Ono-gun, Oita prefecture, Kyushu Region, Japan
Grey, dull, elongated, prismatic crystals to 5cm.
Arsenopyrite from Pribram, Bohemia, Czech Republic
1.5cm Arsenopyrite crystals.
Arsenopyrite from Mina Ojuela, Mapimi, Durango, Mexico
2-3mm crystals within vugs of Pyrite and Arsenopyrite matrix.
Arsenopyrite from Quiruvilca mine, Santiago de Chuco prov., La Libertad dept., Peru
Very sharp short prismatic crystals to 3mm with wedge-shaped terminations and triangular faces. Some of the crystals are short enough to appear pseudo-octahedral.
Arsenopyrite from Hidalgo del Parral, Chihuahua, Mexico
Arsenopyrite crystals to 4mm.
Arsenopyrite from Trepca Valley, Kosovo
Very nice striated Arsenopyrite crystals, well-formed to 7mm perched on Pyrite.