The circular ivory medallion depicts a lady in court dress in profile facing left. Her elaborately dressed hair is held in place by a pearl-headed comb, while the low corsage is decorated with a pendant jewel; she wears a cloak. The signature on the truncation under the right shoulder reads 'Risni 1765'. The ivory background is relatively thin, and the relief may have been fixed to the wood support to guard against possible damage.

This medallion is practically identical to a slightly larger terracotta medallion by Jean-Baptiste Nini (1717-1786) in the Musée des Beaux-Arts du Château at Blois (inv. 861-199-1; diameter 15.5 cm.), signed and dated 'J B NINI F 1762', although there are slight differences in the edging of the dress and in the ornament on the corsage. Other terracotta versions are known in the Louvre (inv. no. RF 4589), the Musée Carnavalet, Paris, at Ecouen (formerly in the collections of the Musée de Cluny), Chaumont, Nevers, and in Edinburgh. Another terracotta version was sold at Christie's, New York on 11 January, 1994, lot 69A, and a 19th-century version was auctioned in Brussels at Pierre Bergé and Associés on 31 May, 2011.

Marie Alcock was the daughter of an English industrialist, Michael Alcock (1714-1785), originally from Birmingham, who settled in La Charité-sur-Loire in 1756, and set up a manufactory of hardware in that town, where Nini was also based. Nini is not known to have been an ivory carver, and the inscription on A.122-1956 suggests that it was executed by another hand after Nini's terracotta, 'Risni' perhaps being a misreading of 'Nini'.