This paper focuses on the characteristics and use of transparent homogenous coloured glass for cast glass sculpture. It provides an overview of glass colouring agents and their characteristics, and establishes factors that influence the appearance of colour in glass. Methods to visually evaluate appropriate colour density for a given form are discussed, as well as essential characteristics that a form must possess to achieve results within a density threshold area, where coloured glass changes in value and/or hue between thick and thin sections.