James Tassie was born in Pollokshaws, Scotland, in 1735. Originally a stonemason, he invented a glass paste composition which he used to create a series of casts of ancient gems, cameos and intaglios made from coloured glass containing potash and lead. His creations were collected by figures such as Catherine the Great of Russia. He also produced numerous portraits of eminent figures from the late 18th century, modelled from life. He sketched around five hundred of his contemporaries.