Galena

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Galena crystals

Description

Egyptian kohl jar
MFA# 1973.663

A gray metallic-like mineral composed of Lead sulfide. Galena commonly occurs as cubic crystals. It is the principal ore source for metallic Lead and often contains significant amounts of Silver. Galena is mined from deposits in Canada, Mexico, England (Cornwall), Australia (Broken Hill), Germany (Clausthal Zellerfeld), Italy, Germany, Romania, Austria, France, Spain, Chile, Peru, Africa, and in the United States (Missouri, Illinois, Iowa, Idaho, Wisconsin, Oklahoma, Kansas, Colorado, California). When crushed, lead sulfide is a black powder. In ancient Egypt, it was known as 'kohl' and was used as a cosmetic. Powdered galena was also used in glazes for medieval pottery and 17th century slipware. In the mid 20th century, it was used as a semiconductor in crystal radio sets. Lead sulfide is still used in some ceramic glazes and as a source for the production of Lead sulfate.

Synonyms and Related Terms

galenite; lead glance; lead sulfide; plumbus sulfide; Bleiglanz (Deut.); Galenit (Deut.); galène (Fr.); galaniet (Ned.); galena (Esp., Port.); galeniet (Ned.)

Raman

GalenaRS.jpg

Risks

Toxic by inhalation or ingestion. Skin contact may cause irritation or ulcers. Carcinogen, teratogen, suspected mutagen.

Fisher Scientific: MSDS

Physical and Chemical Properties

Soluble in nitric acid and hot, dilute hydrochloric acid. Insoluble in water.

Isometric crystal system with cubic crystals. Cleavage=perfect in three directions.

Luster = metallic. Streak = gray. Fracture = subconchoidal, brittle

Composition PbS
CAS 1314-87-0
Mohs Hardness 2.5
Density 7.4-7.6 g/ml
Molecular Weight mol. wt. = 239.27

Resources and Citations

  • G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 443
  • C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
  • Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
  • Henry Hodges, Artifacts: An Introduction to Early Materials and Technology, Ronald P. Frye, Kingston, Canada, 1988
  • Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
  • Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
  • The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 5445
  • Susan E. Schur, Conservation Terminology: A review of Past & Current Nomenclature of Materials, Technology and Conservation, Spring (p.34-39); Summer (p.35-38); Fall (p.25-36), 1985
  • Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
  • CRC Handbook of Chemistry and Physics, Robert Weast (ed.), CRC Press, Boca Raton, Florida, v. 61, 1980 Comment: density=7.3-7.6