The Gemological Institute of America (GIA) plans to introduce cut grades for marquise-, oval- and pear-shaped diamonds next year, marking a long-awaited development for the market.

The diamond industry has been requesting the change for several years, since cut quality can vary greatly, and the GIA currently does not recognize this in its reports.

While round brilliant diamonds can get a triple-Ex grade – excellent cut, polish and symmetry – other shapes get scores only for polish and symmetry.

The GIA intends to launch the cut-grading system for fancies in 2027, initially covering those three shapes, the organization said in a statement to Rapaport News on Friday. It will share additional details about the launch and related laboratory services in early 2027.

“GIA has been working toward developing cut-grade standards for fancy-shape diamonds since the introduction of the GIA round brilliant cut-grading system in 2006,” the statement continued. “This effort is aligned with GIA’s mission of consumer protection and will be supported by GIA education, laboratory services, and manufacturer-focused solutions.”

Tom Moses, GIA’s executive vice president and chief laboratory and research officer, initially revealed the plans last September at the Jewellery & Gem World Hong Kong show, JewelleryNet reported at the time – without specifying with which shapes it would begin.

Fancy-shape demand has grown over the years. Almost a third of diamonds that GIA received for grading in 2022 were fancy-shaped, up from less than a quarter for the previous 10 years, Moses said in a 2025 interview with JewelleryNet.

Fluorescence comments
Separately, the GIA plans to add new comments about fluorescence to its standard diamond grading and dossier reports, beginning in the fourth quarter of this year.

Natural diamonds with D to Z color possessing fluorescence within a certain range will receive one of two notes, the GIA told Rapaport News last week.

One possible comment will say that the fluorescence may enhance the diamond’s appearance in environments rich in ultraviolet (UV) light, such as natural daylight. The other possible comment — which will apply to less than 0.2% of natural, D to Z diamonds — will state that fluorescence “can make existing characteristics unrelated to fluorescence, such as reduced transparency, haziness, or milkiness, more noticeable under UV-rich lighting,” it added.

The GIA is primarily evaluating those two options, which would appear in the comments section of relevant grading reports. It has not finalized the wording, the institute cautioned.

Fluorescence has long been a contentious issue for the diamond industry. Stones with higher levels of fluorescence tend to sell at a discount in the trade because of a perceived impact on desirability.

In a 2021 paper, the GIA argued that strong fluorescence does not itself cause haziness in diamonds but can exacerbate the effect.

However, the new comments on the reports will not say anything about how fluorescence affects the color grade — a connection that the industry has occasionally made.

The phenomenon can cause a lower-color diamond to appear more colorless under (UV) light, according to a post on the GIA website. In high-color diamonds, however, some people perceive a hazy or oily appearance in fluorescent stones, it said.

In total, around 10% of natural, D to Z diamonds that the GIA receives may be eligible for a fluorescence comment, the institute said. Only diamonds with fluorescence within certain intensity ranges, and within specific color, clarity, and polish ranges, will be eligible, it clarified.

“The comment is based on extensive work by GIA researchers into the effect of blue fluorescence on the appearance of diamonds,” it elaborated. “The research demonstrates that fluorescence generally has a neutral-to-positive effect on appearance and, in many cases, may cause a diamond to appear brighter in daylight-equivalent environments.”

Image: Marquise-shaped diamonds. (Shutterstock)

Courtesy: AOJ DESK NEWS