4 Carat Fancy Blue VS2 Radiant Cut Diamond Ring
The center stone is a 3.58-carat Fancy Blue VS2 Radiant cut natural diamond, GIA certified (Rosenberg ref. 96523). Fancy Blue diamonds at this carat weight are among the rarest configurations in the colored diamond market — GIA records indicate that blue diamonds of any grade represent a fraction of a percent of annual fancy color submissions, and those grading Fancy Blue above three carats are rarely encountered in open commerce.
GIA Color Grade: Fancy Blue
GIA grades natural blue diamonds on a scale progressing from Faint through Very Light, Light, Fancy Light, Fancy, Fancy Intense, Fancy Vivid, and Fancy Deep. A Fancy Blue grade confirms consistent, face-up blue saturation achieved through the stone’s body color — typically the result of trace boron incorporation during crystal formation rather than surface treatment or enhancement. VS2 clarity places the diamond in the very-slightly-included range: any inclusions present are not detectable by the unaided eye and exert no influence on light performance or structural integrity.
Why Radiant Cut for Fancy Blue Stones
The Radiant cut combines a rectangular outline with a modified brilliant facet pattern that generates substantially higher light return than step cuts. For a Fancy Blue center stone, this facet structure serves a dual purpose: it maximizes face-up color saturation — the primary driver of value in fancy color diamonds — while delivering the brilliance that distinguishes it from the more subdued emerald or Asscher alternatives. The cut’s cropped corners also reduce mechanical vulnerability at the girdle edges without compromising the stone’s visual footprint.
Three-Stone Platinum Setting with Cadillac Side Stones
Two Cadillac-cut side diamonds, 1.27 carats total weight, flank the center stone in a step-cut format that complements the Radiant’s linear profile without generating competing optical activity. The Cadillac’s angled silhouette creates a precise geometric transition between center and shoulder, reinforcing the perceived width of the composition. The mount is handmade platinum — the standard metal for investment-grade fancy color settings due to its neutral white tone, 95% purity, and long-term resistance to prong wear over decades of use.
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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.