The ancient Egyptians attached a special significance to the colour green as it was considered to be associated with life itself. Egyptian green is shown to be produced by variation of the CaO/CuO ratio, kiln temperature and kiln atmosphere used in the production of Egyptian blue. The major minerals synthesised are para-wollastonite and tridymite, indicating a firing temperature of ~1000 °C. Egyptian green was often applied to pottery using beeswax, often over either huntite or a silica slip and, what are called generically “green earths” were applied to cartonnage in a tomb at Kellis cemetery. Alkali-lime glazes, later with added lead to lower the fusion temperature, were applied to pottery surfaces. During the Roman period, a lustre glaze was introduced by the firing under reducing conditions of silver or copper dissolved in vinegar on to a lead-free aluminosilicate glaze.