Tinctures are the colours, metals, and furs used in heraldry. There are nine tinctures in common use: two metals, five colours, and two furs. The metals are or and argent ; the colours gules (red), azure (blue), vert (green), sable (black), and purpure (purple); and the furs ermine, which is derived from the winter fur of a stoat, and vair, which is derived from the fur of a red squirrel. The use of other tinctures varies depending on the time period and heraldic tradition in question.