Pre-Auction Analysis: Sotheby’s Hong Kong, April 25th, 2025

Why Do We Write This Analysis?

Pre-owned Fancy Color diamonds rarely exchange hands, but when they do, it often happens at auctions. Many of these color diamonds come from older jewelry, making it essential to highlight quality nuances that aren’t available elsewhere.

Who can benefit from this analysis?

Our pre-auction articles guide professionals in making informed decisions. Retailers benefit by understanding the reasons behind price differences between the color diamonds they showcase and pre-owned jewelry on the open market, while also recognizing quality variations. These articles also assist dealers seeking to purchase color diamonds without attending the preview.

How We Grade Color Diamonds?

The IDU grading system for color diamonds is straightforward and accessible to all. It assesses three visual attributes not covered in the GIA report: Inner-Grade (richness of color within a defined saturation), Dispersion (how well color is distributed across the face-up view), and Undertone (the color sensation relative to the color as most people imagine it). For those interested in learning more, a brief explanation of the IDU grading is available at the end of this review. For a detailed overview, check out this link.

Who Is Doing the Analysis?

The grading and analysis are conducted by trained FCRF experts who travel to all major auctions. Some lots are analyzed by manufacturers or dealers within the industry after ensuring they have no vested interest in them. To maintain objectivity, we often cross-reference several analyses across multiple experts.

How We Take the Images?

Our experts use the latest iPhone models to capture images of the diamonds during the auction preview. Ensuring that they appear under the same lighting conditions as seen by other viewers. No filters or corrections are applied to the images.

Disclaimer
This analysis reflects the opinions of the FCRF professional team. It does not constitute a recommendation to buy or not buy a particular diamond. Buyers assume the responsibility of verifying any information with the auction house. At times, mistakes can happen in the visual analysis and report placement. Therefore, one should not rely solely on this analysis for buying purposes.