Hexachlorobutadiene is a non-flammable, incombustible, clear, oily and colourless liquid at ordinary temperature and pressure. It is poorly soluble in water but miscible with ether and ethanol. Hexachlorobutadiene is not reported to occur as a natural product. It is chiefly produced as a by-product of the manufacture of chlorinated hydrocarbons where it occurs in the heavy fractions (Hex-waste). The world annual production of the compound in heavy fractions was estimated in 1982 to be 10 000 tonnes.