Son of the architectural historian Sir Howard Colvin, Colvin attended Finchden Manor, Kent in the 1960s where his interest in ceramics and the saxophone developed. After discovering an abandoned kiln in the school grounds, he restored it and dug, prepared and fired his own pots. He subsequently worked with potter Anthony Wakeham at Abingdon, before establishing himself as an independent potter. From the early 1970s Colvin worked at South Newington, Banbury, making useful domestic wares – jugs, mugs and flowerpots, including at least one order of 10,000 pieces for WH Smith. He also started producing architectural models of gothic follies in unglazed red earthenware. He did not sign them because, as he said in a 1973 interview with the Banbury Guardian: “Why should I when there is no one else making them?” At the same time, Colvin's interest in the environment led him to becoming a tree consultant and contractor specialising in conservation, helping him to restore and improve local habitats.