MAISON PAUL ROBIN
Classical Style Brooch
Gold sapphire & diamond
Diameter: 3.5 cm (1.3 in)
Marks: Indistinct maker's mark 'PR' & Eagle's head
French. Circa 1880
Fitted case
Literature: cf. Art Nouveau Jewelry

Vivienne Becker, 1985, p.227
Henri Vever, French Jewelry of the Nineteenth Century
translated from the French by Katherine Purcell, 2001, p.1015