Brass is a bright gold coloured alloy that consists of Copper and Zinc. Brass is a very malleable metal when compared to bronze or zinc and due to a low melting point (900-940 Deg Celsius), is a very easy metal to cast resulting in its use for a large number of household applications.
The colour of brass is determined by the volume of zinc in the alloy, with the more zinc creating a lighter coloured metal. As the zinc levels increase, the resulting alloy is much softer with the softest of brass types (white brass) being too brittle for general use.
Lead or silicone is often added to brass in order to enhance its machinability. Brass with silicone in it cannot be mixed with leaded brass scrap due to safety issues and contamination.