A great way to add 22k Gold to your piece.  For Metal Clay, it is applied to an already fired piece, and must be fired in a kiln.

 

Art Clay Gold Paste (1.5g) is in a viscous liquid form, so that you can add texture or draw directly on the surface of Art Clay Silver (fired piece), ceramic, porcelain and/or glass. This product has 77.5% of indicated weight is 24-Karat gold, and it becomes 22-Karat gold after firing. Art Clay Gold Paste comes in two bottles. One has 1.5gm of thick paste; the other contains a 5ml medium that is used to dilute the paste to a more workable consistency on glazed surfaces. Fires at 800ēC / 1472ēF.