An Italian Grand Ducal jewel casket has beaten its estimate by 414% at a Bonhams San Francisco auction.
The 18th century casket sold for $617,000 against an $80,000-120,000 valuation on October 28.
It was created in the Grand Ducal workshops of Florence, which were owned by the House of Medici - the immensely powerful political and banking dynasty that ushered in the Renaissance.
It features elaborately designed panels inlaid with polished semi-precious stones - a technique referred to as pietra dura.
The previously unrecorded box was probably created under the supervision of Giovanni Battista Foggini (1652-1755), the director of the workshops at the time and an enthusiastic proponent of the pietra dura technique.
Other lots at the sale that performed well included a pair of Regency giltwood mirrors dating to the early 19th century, which realised $26,250.
The willow branch frames feature knotting to the sides along with a depiction of a seahorse in a scallop shell.
A 19th century Louis XVI style gilt-bronze commode a vauntax achieved $25,000.
It is built after a model prominent French cabinetmaker Guillame Beneman (1750-1811) produced for Marie Antoinette. The commode features elaborate marquetry along with gilt panels depicting fauns playing among scrolling vines.
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