Calx

Calx is a residual substance, sometimes in the form of a fine powder, that is left when a metal or mineral combusts or is calcinated due to heat.

Calx, especially of a metal, is now known as an oxide. According to the Phlogiston theory, the calx is the true elemental substance, having lost its phlogiston in the process of combustion.

Miscellaneous Information

• UK Electronic Music artist, Aphex Twin (Richard David James) named some of his songs after different coloured Calx.