An Art Deco diamond ring set within a calibré-cut octagonal onyx surround, in platinum. Marcus & Co. Old European cut center approx. 0.98 ct.; atw. 0.04 ct single cut side diamonds.

One of the preeminent American jewelers of the late nineteenth and twentieth centuries, Marcus & Co. (1892-1962) was a family enterprise from the start. The patriarch of the family was Herman Marcus, who had worked as a court jeweler in Dresden, Germany, a city famous for its Green Vaults filled with bejeweled treasures. In 1850, he immigrated to New York where he designed for Tiffany & Co. and was an important part of the firm's success before leaving to join his sons George and William to form Marcus & Co.