Sep 26 2013
The element arsenic takes its name from the Latin word “arsenicum” or the Greek word “arrenikos” meaning masculine, alluding to the mineral’s potent properties.
Properties of Arsenic
The following are the key properties of arsenic:
- Cell Data
- Space group: R3m (synthetic)
- a = 3.7598(1)
- c = 10.5475(2)
- Z = 6
- Crystal Data
- Hexagonal
- Point group: 3 2/m
- Commonly granular, massive, and in concentric layers
- May be reticulated, reniform, stalactitic
- Rarely columnar or acicular
- As rhombohedra, to 1 mm
- Twinning: Rare on twin plane {1014}; pressure twinning on {0112} develops delicate lamellae
- X-ray powder pattern: 2.771 (100), 3.52 (30), 1.879 (30), 2.05 (20), 1.556 (10), 1.768 (10), 1.757 (7)
- Chemical Composition
Elements |
Content 1 |
Content 2 |
As |
98.14 |
99.1 |
Sb |
1.65 |
0.2 |
S |
0.16 |
- |
insol. |
0.15 |
- |
Total |
100.10 |
99.3 |
- Optical Properties
- Pleochroism: Feeble.
- Anisotropism: Distinct, yellowish brown and light gray to yellowish gray
- R1–R2: (400) 56.0–57.5, (420) 55.1–56.8, (440) 54.2–56.2, (460) 53.3–55.8, (480) 52.7–55.7, (500) 52.4–55.7, (520) 52.0–55.7, (540) 51.7–55.7, (560) 51.5–55.6, (580) 51.2–55.4, (600) 51.0–55.2, (620) 50.8–55.0, (640) 50.6–54.9, (660) 50.5–54.8, (680) 50.4–54.7, (700) 50.4–54.6
- Estimated Properties
Electron density |
Bulk density (electron density) = 5.06 g/cm3
note: Specific gravity of arsenic = 5.74 g/cm3 |
Photoelectric |
PEArsenic = 73.21 barns/electron
U=PEArsenic x ρ electron density= 370.20 barns/cm3 |
Fermion index |
Fermion index = 0
Boson index = 1 |
Radioactivity |
Arsenic is not radioactive |
How to Identify Arsenic
Arsenic as a mineral can be identified in the field by its lead gray, gray, and white color variations. Its opaque form has {0001} perfect cleavage. This mineral has a metallic luster with black streak. The fracture of this mineral is uneven. The density of arsenic is 5.7 g/cm3 with a hardness of 3.5 –approximate to a copper penny. It is non-fluorescent and non-magnetic.
Global Distribution
Arsenic is distributed in the following places:
- Germany - From Freiberg, Schneeberg, Johanngeorgenstadt, Marienberg, and Annaberg, Saxony; Wolfsberg and St. Andreasberg, Harz Mountains; and Wieden, Black Forest
- Czech Republic -At Jachymov (Joachimsthal), Pribram, and Cinovec (Zinnwald)
- France- In the Gabe-Gottes mine, Rauenthal, near Sainte-Marie-aux-Mines, Haut-Rhin
- Romania - From Sacarimb (Nagyag), Hunyad, and Cavnic (Kapnikbanya)
- USA - At Sterling Hill, Ogdensburg, Sussex Co., New Jersey and Washington Camp, Santa Cruz Co., Arizona
- China - From the Dajishan tungsten deposits, Jianxi Province
- Borneo - At Bidi, Sarawak Province
- Japan- In the Akatani mine, Fukui Prefecture
- Peru -In the Huallap´on mine, Pasto Bueno, Ancash Province
Occurrence of Arsenic and Useful Mineral Association
Arsenic occurs in hydrothermal veins and deposits that contain other arsenic minerals. It may also occur in Co–Ag sulfide veins. It is often associated with minerals such as arsenolite, realgar, orpiment, stibnite, cinnabar, galena, pyrite, sphalerite, and barite.
References