realgar

American  

[ree-al-ger, -gahr] / riˈæl gər, -gɑr /

noun

1. arsenic disulfide, As 2 S 2 , found in nature as an orange-red mineral and also produced artificially: used in pyrotechnics.

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realgar British  

/ rɪˈælɡə /

noun

1. a rare orange-red soft mineral consisting of arsenic sulphide in monoclinic crystalline form. It occurs in Utah and Romania and as a deposit from hot springs. It is an important ore of arsenic and is also used as a pigment. Formula: AsS

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Etymology

Origin of realgar

1350–1400; Middle English < Medieval Latin realger ≪ Arabic rahj al-ghār powder of the mine or cave

Example Sentences

I stuck my head inside a cabinet to get a close look at the rocks of the arsenic sulfides realgar and orpiment, blazes of flame orange locked within the crystals.

From The New Yorker • Aug. 27, 2018

Combined with sulphur it forms orpiment and realgar, which are the yellow and red sulphides of arsenic.

From The New Gresham Encyclopedia. Vol. 1 Part 2 Amiel to Atrauli by Various

Many substances were employed in ancient medicine: galena was the basis of a valuable Egyptian cosmetic and drug; the arsenic sulphides, realgar and orpiment, litharge, alum, saltpetre, iron rust were also used.

From Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1 "Châtelet" to "Chicago" by Various

These are orpiment, realgar, acetic acid, artificial camphor, per-iodide of tin, and the chlorides of tin and arsenic.

From Experimental Researches in Electricity, Volume 1 by Faraday, Michael

Both realgar and orpiment were important for pigments, medicinal purposes, and poisons among the Ancients.

From De Re Metallica, Translated from the First Latin Edition of 1556 by Agricola, Georgius