Galena
Galena is a
lead ore. This article describes Galena's mineral properties. In its
chemically purified form, galena is known as
lead sulfide; refer to that article for chemical and industrial uses.
Galena is one of the most abundant and widely distributed sulfide minerals, and is the most common ore of
lead. Crystals are usually cubic, sometimes
octahedral. It is often associated with the minerals
sphalerite and
fluorite. Galena deposits sometimes contain significant amounts of
silver as an impurity, and these galenas have long been the most important ore of silver in
mining.
Encyclopedia
| Galena | | General | Category | Mineral | Chemical formula | lead sulfide | Identification | Colour | Lead gray, silvery | Crystal habit | Cubes, tabular and sometimes skeletal crystals | Crystal system | Isometric hexoctahedral | Cleavage | Cubic | Fracture | Flat to even | Mohs Scale hardness | 2.5 - 2.75 | Luster | Metallic | Refractive index | Opaque | Pleochroism | None | Streak | Lead gray | Specific gravity | 7.4 - 7.6 | Fusibility | 2 |
Galena is a
lead ore. This article describes Galena's mineral properties. In its
chemically purified form, galena is known as
lead sulfide; refer to that article for chemical and industrial uses.
Galena is one of the most abundant and widely distributed sulfide minerals, and is the most common ore of
lead. Crystals are usually cubic, sometimes
octahedral. It is often associated with the minerals
sphalerite and
fluorite. Galena deposits sometimes contain significant amounts of
silver as an impurity, and these galenas have long been the most important ore of silver in
mining.
Galena deposits are found in
France,
Romania,
Austria,
Belgium,
Italy,
Spain,
Scotland,
England,
Australia, and
Mexico. In the
United States it occurs in
Missouri,
Illinois,
Iowa,
Kansas,
Oklahoma,
Colorado,
Idaho,
Utah,
Montana, and
Wisconsin.
Galena is the official state mineral of
Missouri and
Wisconsin,
USA. Galena also occurs at
Mount Hermon in Northern
Israel. In ancient Israel it was used to colour eyes blue.
Uses
Galena was once used as a
semiconductor in
crystal radio sets; combined with a safety pin or similar sharp wire , the galena crystal became part of a point-contact
diode used to detect radio signals.
See also
External links
-
-
- entry for galena
- entry for lead
- mineral deposits
