The Mineral arsenic
Arsenic almost always contains some antimony. Nickel, silver, iron, and sulfur are also commonly found in a given specimen. On a fresh or preserved surface, Arsenic has a tin-white color, but otherwise tarnishes dark gray.
Arsenic and Antimony are almost identical. In many instances, the only way to tell them apart is by conducting complex scientific tests. Stibarsen, a mixture of arsenic and antimony, is also indistinguishable through common methods.
Arsenic is poisonous, and therefore hands should be washed after handling specimens. Fumes are highly toxic, and should never be breathed.
Color
Tin-white. Oxidizes dark gray to black. May also be banded with white lines.
Properties
Streak
Black |
Hardness
3 - 4 |
Transparency
Opaque |
Specific Gravity
5.6 - 5.7 |
Luster
Metallic |
Cleavage
1,1 - basal. Cleavage is rarely observed since crystal faces are uncommon. |
Fracture
Uneven |
Tenacity
Brittle |
Other ID Marks
1) Gives off a garlic odor, especially when struck or heated
2) Tarnishes dark gray |
Varieties
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Rare, orthorhombic polymorph of Arsenic. Arsenolamprite crystallizes in the orthorhombic system, whereas Arsenic crystallizes in the hexagonal system. Arsenolamprite has the same exact same properties of Arsenic, excluding the crystal system, which scientifically defines it as a separate mineral from Arsenic.
Uses
Arsenic is an ore of the element arsenic, although most arsenic comes from arsenic compounds, which are much greater in abundance. Most Native Arsenic specimens are sold to collectors rather than used for industrial purposes.
Arsenic as a commodity is largely used in the manufacturing of glass. It eliminates the initial green color in glass caused by iron impurities. It has been used in the past as a poison, and continues to be used as an insecticide. It has also been previously used for medicinal purposes. It is used electronically in the structure of lasers and semiconductors. It is also used as a coloring agent for paint and fireworks.
Noteworthy Localities
Most collectible Arsenic specimens come from various mines in Europe. The best localities include Príbram and Jáchymov, Bohemia, Czech Republic; St. Andreasberg and Schneeberg, Saxony, Germany; the Ste-Marie-aux-mines in Alsace, France; Kapnick, Romania; and the Storliden mine, Lappland, Sweden.
Arsenic is found in visible crystals at the Akadani mine, Fukui Prefecture, Japan; and at the the Kusa Mine, Bau, Borneo, Malaysia. In North America, Arsenic is found at Washington Camp, Santa Cruz Co., Arizona; and Atlin, British Colombia, Canada.
Distingushing Similar Minerals
Antimony and Stibarsen are indistinguishable from Arsenic through common testing methods, and can only be distinguished with complex scientific tests.