22.10 Carat Sugarloaf Tanzanite Diamond Platinum Ring

The monumental 22.43-carat cushion-cut tanzanite in this convertible ring displays the incredible deep violetish-blue hue for which tanzanites are so desired. The rare gemstone has b...

A pear-shaped tanzanite weighing 5.53 carats is set in this classic ring. The violetish-blue gem is certified by the American International GemLab, and diamond accents add further br...

A brilliant-cut sapphire displays a deep royal blue hue in this elegant ring. The 7.10-carat sapphire at the heart of this classic ring is certified by the Gemological Institute of A...

An incredible contemporary design by the legendary Cartier sets apart this exceptional bypass ring. Crafted of 18k yellow gold, the piece is designed as t...

Diana Ring Elegant. Regal. Distinctive. This ring commands attention with a 10.08 ct untreated tanzanite—loop clean and richly saturated in violet-blue, radiating depth and sophistication. Its silhouette is balanced by two GIA-certified trapeze-cut diamonds (0.31 ct F VS1 and 0.30 ct D VVS1), highlighting the vivid color without distraction. The Diana Ring embodies SONYA K.’s signature blend of bold structure and refined elegance.
Handcrafted in platinum with a European shank for elevated comfort...

This piece comes directly from the vault of Atlantic Diamond Company—a family-run fine jewelry house with nearly 50 years of history serving elite collectors, retailers, and dealers across the country. As the founder shifts focus to new ventures, he’s releasing a final selection of investment-grade gemstone and diamond pieces—offered exclusively to 1stDibs buyers at exceptional, below-market prices. This is not a liquidation or sale—it’s a one-time opportunity to acquire legacy-level jewelry at true insider value. Each piece is final; once sold, it will not be restocked. This is a cocktail ring that showcases a 1.38 carat cushion cut tanzanite. It has diamonds around the gemstone totaling .57 carats. Designed in brightly polished platinum, this gorgeous ring...

Ladies Art Deco diamond ring with 2.56 carat round natural Tanzanite. There are 16 single cut diamonds and six baguette diamonds, H-I in color and SI1-I1 in clarity. The ring is a s...

Tourmaline and diamond cocktail ring. Natural green rectangular 10.85 carat custom cut tourmaline in a solid platinum custom made setting with 8 round cut accent diamonds. 1 recta...