from
The Collaborative International Dictionary of English v.0.48
Orpiment \Or"pi*ment\, n. [F., fr. L. auripigmentum; aurum gold
+ pigmentum pigment. Cf. {Aureate}, {Pigment}, {Orpin},
{Orpine}.] (Chem.)
Arsenic sesquisulphide, produced artificially as an amorphous
lemon-yellow powder, and occurring naturally as a yellow
crystalline mineral; -- formerly called {auripigment}. It is
used in king's yellow, in white Indian fire, and in certain
technical processes, as indigo printing.
[1913 Webster]
Our orpiment and sublimed mercurie. --Chaucer.
[1913 Webster]
{Red orpiment}, realgar; the red sulphide of arsenic.
{Yellow orpiment}, king's yellow.
[1913 Webster]