Realgar orange

Realgar orange natural pigment powder

Realgar is a natural orange-red arsenic sulfide. It is chemically closely related to Orpiment. These two minerals are often found in the same deposits. Undesirable reactions with white lead and red lead are possible. 

Chemical description: Arsenic sulfide, a natural mineral.

Chemical formula: As₄S₄

Light-resistance 6.7

Alkali resistance: 5

Lime Resistance: 5

Acid resistance: 5

Suitability Acrylic, Tempera, Watercolor / Gouache, Oil

Color: bright orange