Cinnabar

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Cinnabar

Description

Cinnabar

A soft, dense, red, native ore composed of mercuric sulfide. Cinnabar is widely distributed around the world and is most often found in veins near volcanic rocks or hot springs. It has been mined from the Spanish cliffs near Almadén for over 2000 years. Other deposits are found in Italy (Iudrio), Germany, Austria, Yugoslavia, China (Hunan, Kweichow), Turkestan, Mexico, Peru (Huancavelica) and the United States (Texas, California, Nevada). Cinnabar was finely ground for use as an artist pigment since antiquity. Red mercuric sulfide has been made made synthetically since at least the 8th century in Europe and possibly earlier in China. Synthetic mercuric sulfide is called Vermilion. Due to impurities, vermilion was favored over ground cinnabar as a red pigment. When exposed to ultraviolet light, mercuric sulfide darkens as a portion changes from its normal red crystalline form to a black isomorph. This can result in splotchy discolorations.

Cinnabar at 100x (visible light on left, UV light on right)

Synonyms and Related Terms

red mercuric sulfide; Pigment Red 106; CI 77766; Zinnober (Deut.); Zinnoberersatz (Ned.); cinabrio (Esp.); cinabre (Fr.); cinabro (It.); cinábrio (Port.); cinnaber (Ned.); shinsha (Jap.); tan-sha (Chin.); sulfure de mercure (Fr.); Chinese vermilion; English vermilion; vermilion (synthetic pigment); red sulfuretted oxide of mercury; liver ore

Raman (MFA)

Cinnabar (Forbes MFA 158) 50X (640x445).jpg

XRD

PIG154.jpg

SEM

F154sem.jpg

EDS

F154edsbw.jpg

Risks

  • Highly toxic by ingestion, inhalation and skin absorption.
  • Darkens in ultraviolet light.
  • Kremer-Pigmente: MSDS

Physical and Chemical Properties

  • Soluble in aqua regia. Unaffected by alkalis.
  • Hexagonal crystal system.
  • Perfect cleavage in three directions (60 and 120 degree angles).
  • Streak = scarlet.
  • Fracture = subconchoidal to uneven.
  • Luster = adamantine to dull.
  • Ground cinnabar has uneven sized fractured particles and may contain quartz.
  • Transmitted light color is cherry red.
Composition HgS
Mohs Hardness 2.0 - 2.5
Density 8.10-8.176 g/ml
Refractive Index 3.146; 2.819

Resources and Citations

  • R.Gettens, R.Feller, W.Chase, "Vermilion and Cinnabar", Artists Pigments, Volume 2, A. Roy (ed.), Oxford University Press: Oxford, 1993. ° Mineralogy Database: Cinnabar
  • R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966 Comment: density = 8.1; ref. index = 3.146; 2.819
  • G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 200
  • Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
  • Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
  • Henry Hodges, Artifacts: An Introduction to Early Materials and Technology, Ronald P. Frye, Kingston, Canada, 1988
  • C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
  • CRC Handbook of Chemistry and Physics, Robert Weast (ed.), CRC Press, Boca Raton, Florida, v. 61, 1980 Comment: density=8.12
  • Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
  • 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 American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
  • 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