Two Tassie glass paste portrait medallions, 1792

oval, the first of Robert Blair, with hair en queue and frilled cravat,  the other of Benjamin Bell, with short curly hair, each signed Tassie F., with name and date on the truncation, on smoked glass over blue card, each with turned pearwood frame

John Gray, James and William Tassie, London, 1894, cat. 33 & 41.

Robert Blair; with inked biography on the reverse. good condition. Benjamin Bell; Frame currently detached but otherwise good condition.
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James Tassie (1735-1799) was born in Pollokshaws, near Glasgow, of Italian origin according to their family tradition. He worked as a stonemason before moving to Glasgow to study art, especially sculpting and modelling and was one of the most distinguished students: 'The pastes by Mr Tassie, in imitation of precious stones, are now generally known as well as his casts in sulphur. Nor does he confine himself to mechanical parts, but imitates original nature with success.' (Gray, op. cit., p. 4).

He then moved to Dublin where he met Dr. Quin who took him as his assistant. They  invented the 'white enamel composition', a vitreous paste unique and admirable by its texture and hardness. Tassie moved to London in 1766 to try his fortune. After a few difficult years, he improved considerably his techniques and casts and encountered success. In addition to his impressions from antique gems, Tassie executed many large profile medallion portraits of his contemporaries, modelled in wax from life,then cast in his white paste. He exhibited at the Royal Academy from 1769 to 1791, published a first catalogue in 1775 and then in 1791. He received many commissions accross Europe, including a large commission of 15,000 examples from Catherine II of Russia which was delivered in four lots in 1781. 
When Tassie died in 1799, his work numbered about 20,000 pieces. His nephew William took over his business.

Robert Blair (1741-1811) was Lord President of the College of Justice.
Benjamin Bell (1749-1806) is regarded by many as the “father of the Edinburgh Surgical School", who was the first to establish an international reputation for Edinburgh Surgery. He published medical works of significance, notably his surgical textbook A System of Surgery which became a best seller throughout Europe and in America. Another example of Tassie's portrait medallion is in the Scottish National Portrait Gallery and a wax version is at The Royal College of Surgeons of Edinburgh.