'Magenta Disk, Red Edge' (1970) features a bold magenta circular form against contrasting elements, showcasing what Heron believed was the inseparable relationship between colour and shape. The composition reflects his principle that "the picture is not the vehicle of meaning: the picture is the meaning". Created in 1970, when St Ives had become a world centre for modernist innovation, this work represents Heron's distinctive British response to Abstract Expressionism. Heron actively engaged with international artistic developments while maintaining his unique vision of colour, space, and light.