20 Carat D Flawless Cushion Cut Diamond Ring
The center stone is a 20-carat D Flawless Cushion cut natural diamond, GIA certified (Rosenberg ref. 700818). Diamonds combining D color with Flawless clarity at twenty carats are encountered only a handful of times per decade in the international market — GIA submission records for this grade combination at this weight represent a structurally finite category, constrained equally by rough availability and the precision required during cutting to preserve both attributes simultaneously.
GIA Grading: D Color and Flawless Clarity
D is the highest position on the GIA D-to-Z color scale, indicating complete absence of detectable body color even under 10× magnification against a standardized white background. Flawless clarity — the highest grade GIA assigns — certifies that no inclusions or surface blemishes are visible to a skilled grader at 10× magnification. At twenty carats, maintaining both grades requires structural perfection through the full depth of the rough crystal; the slightest internal feature or residual color trace at this mass eliminates the stone from either grade category during the evaluation process.
Why Cushion Cut at This Scale
The Cushion cut combines a square-to-rectangular outline with rounded corners and a mixed brilliant facet structure, a format that was the dominant cutting style for exceptional stones throughout the nineteenth and early twentieth centuries. For a D Flawless diamond of this weight, the Cushion’s larger table and open facet planes allow the clarity grade to read visually at face-up, while the modified brilliant pattern maintains scintillation across the stone’s full surface area. The rounded corner geometry also reduces stress concentration at the girdle edge — a relevant structural consideration at this carat weight.
Handmade Platinum Three-Stone Setting
The center diamond is set in a handmade platinum three-stone mount flanked by two side stones. Platinum is the standard metal for D-color diamonds: its neutral white tone introduces no color reflection into the pavilion, preserving the color grade as it reads face-up. At 95% purity, platinum also resists prong deformation over decades of wear — a material requirement for a setting designed to secure a stone of this caliber over its full service life.
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Care
Preserve the brilliance of your diamond through proper care. We recommend professional cleaning annually and safe storage in a jewelry box or pouch. Avoid exposure to harsh chemicals and extreme temperatures. Learn more about our complete care guide for detailed maintenance and storage best practices.
Warranty
Every Rosenberg piece comes with a warranty covering craftsmanship and authenticity. Our warranty protects against manufacturing defects and ensures your diamond’s certified quality. For warranty details, claims, or to register your purchase, contact our specialists.
Delivery
Your diamond is shipped via insured, tracked delivery with full insurance coverage included. Packages are carefully packaged in premium materials and require a signature upon delivery. Review our shipping and delivery policy for complete details about timelines and handling.