from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. A soft orange-red arsenic ore, As2S2, used in pyrotechnics and tanning and as a pigment.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A mineral, arsenic sulfide (AsS), often associated with orpiment and stibnite in lead, silver and gold ores.

from the GNU version of the Collaborative International Dictionary of English

  • n. Arsenic sulphide, a mineral of a brilliant red color; red orpiment. It is also an artificial product.

from The Century Dictionary and Cyclopedia

  • n. Arsenic disulphid (As2S2), a combination of an equal number of sulphur and arsenic atoms; red sulphuret of arsenic, which is found native in transparent crystals, and also massive.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. a rare soft orange mineral consisting of arsenic sulphide; an important ore of arsenic


Middle English, from Medieval Latin, from Catalan, from Arabic rahj al-ġār, powder (of) the mine or cave : rahj, powder + al-, the + ġār, cave; see ġrr in Semitic roots.
(American Heritage® Dictionary of the English Language, Fourth Edition)
Old English, from Medieval Latin, from Arabic رهج الغار (rahj-al-ğār, "cave dust"). (Wiktionary)


  • Several other, less-common minerals contain arsenic, including orpiment, realgar, and enargite, which are arsenic sulfides.


  • Among the items quickly snapped up was an exquisite orange and yellow glass piece made to imitate realgar, a poisonous mineral that is almost pure sulphide of arsenic, beautiful to the eye but poisonous to the touch (price: around €2,000).

    In Maastricht, No Sign of Crisis

  • Such are the kinds of stones that cannot be melted, and realgar, and ochre, and ruddle, and sulphur, and the other things of that kind, most


  • Mix together realgar and orpiment; some object to this mixture on account of the poisonous nature of the ingredients.

    Young's Demonstrative Translation of Scientific Secrets

  • This is procured by mixing massicot, or Naples yellow, with a small quantity of realgar, and a very little Spanish white.

    Young's Demonstrative Translation of Scientific Secrets

  • ~ Arsenic occurs in considerable quantities in nature as the native element, as the sulphides realgar (As_ S_ ) and orpiment

    An Elementary Study of Chemistry

  • Orange-coloured grounds may be formed by mixing vermilion or red lead with King's yellow, or orange lake or red orpiment (? realgar) will make a brighter orange ground than can be produced by any mixture.

    Handbook on Japanning: 2nd Edition For Ironware, Tinware, Wood, Etc. With Sections on Tinplating and Galvanizing

  • Take of nitrate of baryta, twenty-seven parts, by weight; of sulphur, thirteen; of chloride of potassa, five; of realgar, two; and of charcoal three parts.

    Home Pastimes; or Tableaux Vivants

  • It occurs as metallic arsenic, which is of a steel-grey colour, brittle, and gives off a garlic-like odour when heated; as arsenious acid; in the form of two sulphides -- the red sulphide, or realgar, and the yellow sulphide, or orpiment; and as arsenite of copper, or Scheele's green.

    Aids to Forensic Medicine and Toxicology

  • The orange-red sulphides of arsenic, orpiment and realgar, are formed both as primary minerals of igneous source and as secondary products of weathering.

    The Economic Aspect of Geology

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