Our Sotheby’s Important Jewels Pre-Auction Analysis focuses on elements that are not always visible to the untrained eye. We discuss characteristics such as Inner-Grade, Color Dispersion, and Undertone – collectively termed IDU. Professionals use the IDU method intuitively when analyzing a Fancy Color Diamond. The acronym we use makes these elements easier to remember.
Members who read this analysis should see it as a valuable supplement to the GIA report. A detailed explanation of the FCRF’s grading methodology can be found at the end of this article. We recommend reviewing it closely to broaden one’s professional vocabulary for describing fancy color diamonds to clients. We analyze and grade diamonds under LED lights and relative to their grade on the GIA report.
The Grades; FCRF use grades 1, 2, 3, and 4, with 1 being the lowest grade. Grade, 4+ is granted in rare cases and denotes diamonds with exceptional characteristics. Diamonds that receive a minimum total IDU score of 9 without a red remark pass the industry premium threshold and can be traded easily. Fancy Color Diamonds that are graded 10 or above (without a quality remark) are usually sought after by high-end jewelers and collectors.
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Heera Zhaveraat (HZ International) A Diamond, Watch and Jewellery Trade Promotion Magazine provide dealers and manufactures with the key analytical information they need to succeed in the luxury industry. Pricing, availability and market information in the Magazine provides a critical edge.
