Clars Auctions Offers Art Deco Platinum Ring With 4.92-Carat Diamond

At Clars Auctions' "Antique Diamonds: A Collector's Auction" on March 19, the room's most commanding presence was a platinum ring from the Art Deco period, its center stone a 4.92-carat F-color, VS2-clarity cut-cornered square step-cut diamond carried to market with a presale estimate of $50,000 to $70,000.

The geometry of that stone is worth pausing on. A cut-cornered square step-cut, with its stacked parallel facets and clipped corners, is precisely the silhouette Art Deco designers favored: architectural, disciplined, and brilliantly legible in platinum's cool, white light. The ring's maker surrounded the center stone with 26 single-cut diamonds set among delicate etched scrollwork, bringing the estimated total diamond weight to 5.20 carats within a mounting that weighed just 4.85 grams. That lightness is a signature of platinum craftsmanship at its best — the metal strong enough to hold the stones with minimal material, letting the diamonds carry the visual weight entirely.

The second-ranked lot, a Facadoro diamond and 18k gold opera-length necklace estimated at $25,000 to $35,000, offered a counterpoint in scale and warmth. Where the Art Deco ring was cool and compact, the Facadoro piece commanded attention through length and volume.

Below those two anchors, the sale assembled a diverse survey of periods and materials. An antique diamond and silver-topped 14k gold brooch set with rose-cut diamonds carried an estimate of $10,000 to $20,000 — rose cuts being among the most historically resonant of diamond forms, their domed profiles and flat bases predating the modern brilliant by centuries. An antique sapphire and 18k ankle bracelet was estimated at $10,000 to $15,000. A Colombian emerald, seed pearl, diamond, and 18k gold necklace came in at $3,000 to $5,000, and a color-changing alexandrite ring, that rarest of gems in fine quality, was estimated at $3,000 to $6,000. Fine jade pieces and a group of rare and limited-edition Rolexes rounded out the offering.

The sale also drew on an exceptional source of consignment: select property from the San Francisco Opera, lending certain lots a provenance with genuine cultural resonance beyond their gemological credentials. The broader catalog spanned Georgian, Victorian, Art Deco, and Retro periods, representing nearly two centuries of jewelry-making tradition in a single afternoon sale.

For a market that has grown increasingly attentive to period craftsmanship, the Clars offering illustrated what separates a curated antique sale from a generalist auction: not just the presence of important stones, but the coherence of the collection around them.