Art Deco Platinum Sunburst Ring (c. 1935–1941) with 1.54 ct Black Diamond & Approx. 1.00 ct Antique Single-Cut Diamond Halo

This striking platinum ring dates to the late Art Deco / early Retro period, circa 1935–1941, a time when American jewelry design evolved from geometric restraint into more sculptural, dimensional forms. The piece is a strong example of the era’s sunburst or starburst motif, one of the most recognizable design languages of the late 1930s.

At the center is a 1.54 carat black diamond, a later replacement stone secured by non-original prongs. While not part of the original construction, it now anchors the dramatic radiating composition and emphasizes the bold, graphic nature of the setting. The original design likely held either a large Old European Cut diamond or a richly colored gemstone such as sapphire or ruby, both commonly used in high-end starburst designs of the period.

Encircling the center is a halo of approximately 1.00 carat total weight of antique single-cut diamonds, each set in individual prongs. These stones are consistent with late 1930s American manufacturing, where single cuts were the standard for fine accent work. Their presence in original settings provides strong evidence of authenticity, as modern reproductions would typically use full-cut melee.

The defining feature of this ring is its radiating sunburst/starburst platinum head, where elongated platinum “rays” extend outward from the center stone. This sculptural design reflects the transitional aesthetic between late Art Deco and early Retro jewelry, combining geometric symmetry with increased dimensionality and movement.

The shoulders of the ring are equally significant, featuring elongated navette-shaped diamond panels bordered with milgrain detailing and set with pavé single-cut diamonds. This architectural treatment is highly characteristic of American jewelry from approximately 1935–1942 and represents a shift toward the more bold, structured aesthetic of the coming Retro era.

A split shank flows into the shoulder design, further reinforcing the transitional nature of the piece. This combination of structure, ornamentation, and volume is far more complex than earlier Art Deco designs, signaling the increasing influence of sculptural form in late-1930s jewelry.

The ring is stamped “10% IRID/PLAT,” an important and highly diagnostic hallmark of American platinum jewelry from the pre-WWII era. This designation indicates a platinum-iridium alloy, commonly used between roughly 1900 and the late 1930s before postwar standards shifted toward different alloy systems and “950 PLAT” markings became dominant. The presence of this stamp strongly supports a pre-1940s origin.

Despite later modifications to the center stone and prongs, the ring’s underlying structure remains intact and strongly consistent with authentic late Art Deco American craftsmanship. The original single-cut diamonds, milgrain detailing, platinum construction, and starburst architecture all align cohesively with this period.

This is a bold, high-impact example of transitional American jewelry design, combining Art Deco geometry with the emerging glamour and dimensionality of the early Retro era.

Details

• Era: Late Art Deco / Early Retro
• Date: Circa 1935–1941
• Metal: Platinum
• Hallmark: “10% IRID/PLAT” (platinum-iridium alloy)
• Center Stone: Black diamond (later replacement)
• Center Stone Weight: 1.54 carats
• Accent Stones: Antique natural single-cut diamonds
• Total Accent Diamond Weight: Approx. 1.00 carat
• Setting Style: Radiating sunburst / starburst platinum head
• Halo Design: Prong-set single-cut diamond halo
• Shoulders: Navette-shaped diamond panels with milgrain borders and pavé single cuts
• Shank: Split shank with flowing architectural transitions into shoulder panels
• Gallery: Open, dimensional platinum construction with sculptural elevation
• Craftsmanship: High-quality American pre-WWII platinum fabrication
• Original Design Note: Likely originally set with a large Old European Cut diamond or colored gemstone center
• Condition Notes: Original platinum mount and accent diamonds intact; center stone and prongs are later modifications
• Authenticity: Strongly consistent with genuine late Art Deco / early Retro American manufacture

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