Missouri Symbols
Missouri State Mineral
Galena
(lead)
Adopted on July 21, 1967.
On July 21, 1967, the mineral galena was adopted as the official mineral of Missouri. Galena is the major source of lead ore, and the recognition of this mineral by the state legislature was to emphasize Missouri's status as the nation's top producer of lead. Galena is dark gray in color and breaks into small cubes. Mining of galena has flourished in the Joplin-Granby area of southwest Missouri, and rich deposits have been located in such places as Crawford, Washington, Iron and Reynolds counties. (RSMo 10.047) .
Missouri State Mineral: Galena
Galena is the primary ore mineral of Lead. Worked for its lead content as early as 3000BC, it is found in ore veins with Sphalerite, Pyrite and/or Chalcopyrite, and in Sedimentary rocks as beds or impregmentations. The crystals are bright when fresh but often receive a dull tarnish after exposure to air.
Galena is a common and popular mineral for rock hounds. Its characteristic cubes, distinctive cleavage and high density make it easy to identify and a favorite in high school geology labs. The structure of Galena is identical to that of halite, NaCl. The two minerals have the same crystal shapes, symmetry and cleavage. Some Galena may contain up to 1% silver in place of lead. The large volume of Galena that is processed for lead produces enough Silver as a by product to make Galena the leading ore of Silver.
Galena (lead) What starts our cars?
About 80 percent of mined lead goes into making vehicle batteries. Approximately 1,000 pounds of rock containing galena must be mined a processed for
the 30 pounds of lead in each car battery. Lead is also used in our televisions and computer screens because lead stops radiation. Lead is not used
in pencils. Pencils are made from another mineral called graphite. Approximately 90 percent of lead produced in the Untied States comes from Missouri,
ranking it first in the nation. Also, the largest smelter, a large processing facility that gets lead from galena, is located in Missouri.
GALENA PHYSICAL CHARACTERISTICS:
Galena, also called lead glance, is the natural mineral form of lead(II) sulfide. It is the most important ore of lead and an important source of
silver.
Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms.
It is often associated with the minerals sphalerite, calcite and fluorite.
- Color is lead to silver gray sometimes with a bluish tint.
- Luster is metallic to dull in weathered faces.
- Transparency crystals are opaque.
- Crystal System is isometric; 4/m bar 3 2/m
- Crystal Habits include the cube, octahedron and combinations of the two. Spinel twinning is possible forming flattened crystals. Also massive and granular.
- Cleavage is perfect in four direction forming cubes.
- Fracture is uneven and rarely seen because of the perfect cleavage.
- Hardness is 2.5+
- Specific Gravity is approximately 7.5+ (heavy even for metallic minerals)
- Streak is lead gray
- Associated Minerals are calcite, dolomite, sphalerite, pyrite and other sulfide minerals, also lead oxidation minerals such as cerussite and anglesite.
- Other Characteristics: brighter metallic luster on cleavage surfaces than on crystal faces.
- Notable Occurances include Texas-Oklahoma-Missouri area, USA; Germany, Peru, Mexico, Zambia, and England.
- Best Field Indicators are crystal habit, cleavage and, perhaps most importantly, density.
Missouri Law
The law designating the mineral "galena" as the official Missouri state mineral is found in the Missouri Revised Statutes, Title 2, Chapter 10, Section 10.170
TITLE II SOVEREIGNTY, JURISDICTION AND EMBLEMS
Chapter 10
State Emblems
Section 10.047
August 28, 2013
State mineral.
10.047. The mineral "galena" is the official mineral of Missouri.
(L. 1967 p. 93 § 1)
Minerals, & Gems
Gemstone, Minerals, Rocks
