Solubility
INSOL IN WATER, ACID; SOL IN POTASSIUM CYANIDE, HOT SULFURIC ACID;Soluble in aqua regia, insoluble in acids;Dissolves readily in 3:1 hydrochloric-nitric acid to form HAuCl4; dissolves in cyanide solutions in the presence of air or hydrogen peroxide to form Au(CN)2
Color Form
Soft, yellow metal;Cubic, yellow, ductile, metallic crystals; forms red, blue, or violet colloidal suspensions.;Yellow, ductile metal, relatively soft;Yellow, soft metal, face-centered cubic structure;Malleable, lustrous, yellow metal;When prepared by volatilization or precipitation methods, deep violet, purple, or ruby powder
Stability
Extremely inactive; not attacked by acids, air or oxygen. Superficially attacked by aq halogens at room temp.;Does not corrode in air, but is tarnished by sulfur;...Stable in basic media.