About
Crystal Forms & Aggregates
Other ID Marks
2) Triboluminescent.
Complex Tests
Striking Features
Environment
Varieties
✓ common · ✗ uncommon
- Danaite— Cobalt-rich variety of Arsenopyrite, in which the cobalt may replace as much as 12 percent of the iron. Found in Franconia, New Hampshire.
- Gudmundite— Mineral almost identical to Arsenopyrite, but contains antimony in place of the arsenic. Its chemical formula is FeSbS. Gudmundite is very similar in physical properties to Arsenopyrite, and is sometimes wrongly classified as a variety of it, when in fact it is scientifically a separate mineral species. It is found in Gudmundstorp, Sala, Sweden, and Ilimaussaq, Greenland.
Uses
Noteworthy Localities
Important European localities for Arsenopyrite include Panasqueira, Portugal; Freiberg, Saxony, Germany; Trepca, Kosovo (former Yugoslavia); and several of the ore deposits in the Cornwall area in England. In South America, fine Arsenopyrite crystals have come from Potosi, Bolivia; and the Pachapaqui District, Ancash Dept., Peru. Mexico also contains several notable occurrences, especially the Santa Eulalia district, Chihuahua; and Concepcion del Oro, Zacatecas.
In the U.S., Arsenopyrite localities include Mount Mica, Oxford Co., Maine; Roxbury, Litchfield Co., Connecticut; Lewis, Essex Co., New York; Franklin, Sussex Co., New Jersey; Leadville, Lake Co., Colorado; and the Cleveland mine, Stevens Co., Washington. Fine specimens were once found Carmel, Putnam Co., New York. The cobalt-rich variety, Danaite, comes from Franconia, Grafton Co., New Hampshire. In Canada, Arsenopyrite is found in the Cobalt area, Timiskaming District, Ontario; and in the Nickel Plate Mine, British Columbia.
Common Mineral Associations
Distinguishing Similar Minerals
Loellingite - Very hard to distinguish, but lacks the sulfur attributes of Arsenopyrite.
Cobaltite - Occurs in different crystals.
Photos
See all 13 photos →Crystal forms
Drag to rotate, scroll to zoom.