Aluminium Gold
One part of aluminium to 99 of gold gives a metal the color of green gold, very hard but not ductile. An alloy of 5 parts of aluminium to 95 parts of gold gives an alloy that is nearly as brittle as glass. An alloy of 10 parts of aluminium to 90 parts of gold is white, crystalline and brittle. An imitation of gold, used as a substitute for the precious metal in cheap jewelry, is made by fusing together 5 to 7 1/2 parts of aluminium, 90 to 100 parts of copper and 2 1/2 of gold. The color of this alloy resembles gold so closely as to almost defy detection.