RENÉ BOIVIN - 1900-1920 TORTOISESHELL BUTTERFLY BROOCH The wings are in very finely regrained brown tortoiseshell. They are set with cabochons of clear sapphires, and the body is studded with gold and set with a pink sapphire. Mounted in 18K yellow and pink gold. French work, unsigned. Gross weight: 15.35 g. Dimensions: 9.7 x 5.2 cm. Attested by Françoise Cailles. A blue and pink sapphires, tortoiseshell and 18K yellow and pink gold butterfly brooch by René Boivin, circa 1900-1920. French assay mark, not signed. Gross weight : 15,35 gr. Dimensions : 9,7 x 5,2 cm. Attestation by Françoise Cailles.