Cuff bracelet, c. 1935, by Suzanne Belperron of carved smoky quartz set with quirkily shaped cabochon sapphires in yellow gold. This was unsigned, as is everything Belperron created. “My style is my signature,” she said. This was true. Who else would make a bracelet like this in the 1930s? But Belperron died in 1983 and her jewelry has skyrocketed in value in recent years. Resale requires serious authentication, preferably by the ultimate expert Olivier Baroin. This sold at Christie’s in Decembe