In 1772 Nini was engaged to supervise the chateau of Chaumont-sur-Loire workshop producing glass and ceramics, owed by Jacques Donatien Le Ray, which allowed him to pursue the production of terracotta medallions.
Interested only in portraits, Nini executed likenesses of his friends, who included many of the most significant figures of the period, including Benjamin Franklin (1777), Louis XV (1770), Maria-Theresa, Empress of Austria (1769 and 1770) and Voltaire (1780), among others. Working only in terracotta from a carved wax mould, Nini modelled about one hundred portraits, but was able to retain the model and produce a large number of medallions. (See S. Scher, Dictionary of Art, 1986, vol. 23, p. 156).