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4.60ct Cushion Grey Blue Spinel 0.33ctw Diamond Platinum Ring
In-store pricing snapshot
Last known warehouse price ยท Sep 16, 2026. Currently out of stock.
* Prices shown are for Costco members only.
This elegant platinum ring features a 4.60-carat cushion-cut grey-blue spinel as its center stone, complemented by 0.33 carats total weight of diamond accents. The cushion cut is prized for its soft, rounded corners and large facets that enhance the stone's natural color and brilliance.
Grey-blue spinel is a rare and coveted gemstone known for its exceptional hardness (8 on the Mohs scale), vivid natural color, and brilliant luster. Unlike many gemstones, spinel is rarely treated, making natural specimens particularly desirable among collectors. The grey-blue hue gives this stone a sophisticated, understated elegance suitable for everyday wear or special occasions.
The setting is crafted in platinum, offering superior durability, natural white luster, and hypoallergenic properties. Platinum is denser and more durable than white gold, ensuring the setting maintains its finish and securely holds the center stone over a lifetime of wear.