Art Deco Onyx and Diamond Ring of Platinum

An Art Deco-era ring dating to 1925–1938, featuring an octagonal onyx plaque framed by a geometric border of diamonds and mounted in platinum. The crisp octagonal silhouette and contrasting black onyx and diamonds are perfect examples of Art Deco, reflecting the period’s fascination with bold geometry, symmetry, and sophisticated contrasts of color and texture. The ring was reshanked in 1977, thoughtfully preserving the original Art Deco plaque and diamond setting while ensuring the piece’s continued wearability.

The ring face measures approximately 0.5 inches in diameter and weighs 2.90 grams. The ring is currently a size 7 and can be professionally resized for an additional charge. It remains in great antique condition.

Gemstone identification has been confirmed using Raman spectroscopy, a non-destructive analytical technique that provides a precise chemical fingerprint to verify authenticity.

Metal authenticity has been professionally verified using XRF (X-ray fluorescence) analysis and traditional jeweler’s acid testing, confirming solid platinum construction.

A sophisticated example of Art Deco design, this ring beautifully pairs the dramatic elegance of onyx with the brilliance of diamonds and the enduring refinement of platinum.