Career
Little is known of his early training, but he started as a modeler at the Sèvres factory. He was sculptor to the Duc d"Orléans and worked on gilded lead statue groups of children at the Palais-Royal. He had a school for sculpture and drawing.
Louis Jean-Jacques Durameau studied there.
Defernex received no official commissions, and his art seems to have been regarded as rather unfashionable. His portrait busts have been compared to those of Jean-Baptiste Greuze and described as "honest, unidealized, quite free from gallant flattery": "All the graces and tender amorous atmosphere that floated about Madame Favart," the singer and actress who was the subject of a 1762 work, "seem dispelled by his convincingly truthful bust of her."
Other works include:
Distressed Spirit (1768), a marble fragment of a funeral monument that was destroyed during the French Revolution;
plaster bust of Georges-Louis Leclerc, Comte de Buffon (1772);
The Milkmaid (1754/60), an example of his Sèvres porcelain, modeled after a work created by François Boucher for Madame de Pompadour"s dairy at Crécy.