Natural diamonds
The fluorescence discount is narrowing in top colours
Strong blue fluorescence used to cut deeper into D-to-F natural prices; that discount has narrowed as buyers grow more comfortable with faint haze risk.
Imperial Star Gems trade desk1 min read
Buyers are paying closer to full price for strongly fluorescent stones in top colour grades than they did a year ago.
- Strong or very strong blue fluorescence has traditionally carried a discount in D to F colour, on concern that it can give a stone a faint hazy look.
- That discount has narrowed as more buyers view the stone in person or on video before purchase, rather than pricing purely from the report.
- The discount remains largest at G colour and below, where fluorescence can make a stone look better than its grade, cutting the other way.
Fluorescence is worth checking in daylight before buying, not just on paper — see fluorescence for what the grading categories mean in practice. Ask us for a video of any stone before you commit.
Market commentary drawn from publicly available market data and trade reporting, not investment advice. Prices move; figures are indicative and correct as of the date above.