The September/October 2025 issue of the GemGuide from Gemworld International features several helpful changes to the sapphire pricing charts, now also available in the GemGuide Pricing app. (Subscription to view pricing charts is required.)
Stuart Robertson, president of Gemworld International, and Research Director for the GemGuide pricing charts, tells us that the heated sapphire, non-origin specific category has been updated with new weight ranges, and prices. Instead of the broader combination weight ranges we’ve seen used in the past charts, stones under 10 carats are now listed in single-carat increments, providing greater precision for valuers. And in the larger weight ranges, we see some new divisions, but some still covering 2 or more carats in a single pricing category. “In the heated sapphires, we still have some combined ranges as the stones get larger,” notes Robertson. “The weight to price scale is less reactive with each incremental increase.” [… again, this is in the heated blue sapphire category – gr]
No-Heat Rarity
The observations made in the “no-heat” categories were a supply reality check, and underscores how rarity affects chart pricing. “In the larger Ceylon no-heat blue sapphires, we still have a few multicarat spreads starting at the 12.00 carat range. This is because the population of goods we were seeing was decreasing as the sizes got larger. And so to have a sufficient number of datapoints to be comfortable in publishing prices, we went with a larger spread than we did in the sub-12 carat cells.”
“In the Burma no-heat category, we actually cut off at 12 carats because the lack of goods made it misleading to publish pricing guidelines for such a slim number of stones.”
And with that note comes a Buyers’ Heads-up
Robertson goes on to point out that, “In the larger, finer goods in any of the no-heat sapphire categories, it’s still a sellers’ market.”
The Details
Corundum, Blue Sapphire (Non-Origin Specific, Heat Treated)
“In the non-origin specific, heat-treated sapphire chart, GemGuide further broke out the rows into smaller size spreads, and added several weight categories above 9.99 carats.”
As for added ranges due to pricing differences, the GemGuide has now split the 5 to 7 carat range into two ranges:
5.00ct. to 5.99ct.
and 6.00ct. to 6.99ct.
In last month’s GemGuide, the weight column ended with the wide range of 10.00ct. to 19.99ct. That has changed, breaking this range into four separate ranges:
10.00ct. to 10.99ct.
11.00ct. to 12.99ct.
13.00ct. to 14.99ct.
and 15.00ct. to 19.99ct.
The reason for this is simple. As Robertson notes, “price jumps between size differences, especially in larger sizes and extra fine goods, have gotten more pronounced.”
Ceylon, No Heat
Similar changes were made in the Ceylon unenhanced sapphire chart. Each single digit carat weight will have its own price chart:
5.00-5.99 carats
6.00-6.99 carats
7.00-7.99 carats
8.00-8.99 carats
and 9.00-9.99 carats ranges.
The 10 to 20 carat range will also be split:
10.00-10.99 carats
11.00-11.99 carats
12.00-12.99 carats
13.00-14.99 carats
15.00-16.99 carats
and 17.00-19.99 carats.
Changes in Burma Unenhanced Chart
In the Burma no-heat sapphire chart, the GemGuide also further uses single carat-size spreads in line with Ceylon sapphires, but has eliminated sizes above 12.99 carats “as material in those sizes are now scarce enough that transactional data was insufficient to produce meaningful pricing guidance for the larger, finer quality sapphires.”
Other Colored Gemstone Pricing Updates
“Meanwhile, there were plenty of price updates in the colored stone charts. Readers should pay attention to the yellow/green chrysoberyl, blue star sapphire, color change sapphire, green sapphire, padparadscha sapphire, unenhanced pink sapphire, blue (indicolite) tourmaline, blue/green tourmaline, pink tourmaline, and red (rubellite) tourmaline charts.”
Also Diamond Pricing from the GemGuide
“In this issue, diamond price charts are unchanged. We expect certain diamond prices to increase in response to tariffs in the coming quarters. However, in the current period, prices are stable. During the pause before implementation of the updated tariff rates, the US diamond industry imported sufficient inventories of goods to manage demand during the season. The GemGuide continues to monitor developments in the trade and will update pricing as appropriate.”
Want to help by proving them with feedback, reach out to Research Director Stuart Robertson at srobertson@gemguide.com or Editor-in-Chief Brecken Branstrator at bbranstrator@gemguide.com to share thoughts or suggestions.
