This stone has two triangle colorless areas on each side. This geometrical appearance is typically seen in Emerald cut diamonds that were polished into a Radiant cut. This is usually done in order to achieve a stronger inner-grade or make inclusions less visible. Low clarity in blue diamonds is rarely seen.
Our Pre-Auction Analysis focuses on elements that are hidden from the unprofessional eye. As always, we will describe the important visual elements for those who cannot attend the preview. We will discuss characteristics such as Undertone, Color Dispersion, and Inner-Grade (UDI; a detailed explanation appears at the bottom of this article) the total UDI visual grade is mention under each chart.
We use grades 1, 2, 3, and 4, 1 being the lowest grade. Grade 4+ is granted in rare cases and stands for stones with an exceptional characteristic. Stones that receive a minimum total UDI score of 8, with a ✔ , are mostly suitable for high-end jewelry, collectors and the investment community.
For your convenience, we have added direct links for the GIA reports.
- All images in this article review were taken with an iPhone 10, no filters were applied.
- All auction valuations are per carat and in US Dollars.
Sotheby’s, Hong Kong Magnificent Jewels and Jadeite, April 2nd, 2019
Lot #1798

3.32 carat Fancy Vivid Blue cut-cornered rectangular step-cut, IF
High catalog estimation: $2,302,409 per carat
Price Realized: Didn’t reach the minimum
According to the FCRF rarity data, vivid blue Emerald cut diamonds in this specific size and
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