Colour development of gold ruby alkali silicate glasses, when various elements are added to the batch, has been investigated. Elements used in the study are selenium, iron, tin, lead, antimony, cerium, titanium and bismuth. The colours are presented and compared by their L a b coordinates. Among the elements, selenium and iron are found to be important, and the role of these elements in colour development is discussed. Thermodynamic calculations show that important oxidation states are Fe2+ for iron and Se0 and Se2- for selenium, and that higher melting temperature improves the colour, as it affects the oxidation states of both Fe and Se.