GIA elevate gemological standards for pearls
The Gemological Institute of America (GIA) is set to implement a new, more detailed nacre grading scale across all its pearl classification reports, a significant move for the pearl industry. This development represents an evolution of the GIA’s established GIA 7 Pearl Value Factors™ pearl evaluation framework and is intended to offer finer distinctions in nacre quality.
History
Previously, nacre—a critical factor for a pearl’s aesthetic appeal and durability—received a straightforward grading of either “Acceptable” or “Unacceptable.” An “Acceptable” grade indicated that the nacre was commercially sound in terms of its thickness and condition. Conversely, “Unacceptable” was applied to nacre that presented risks to the pearl’s structural integrity, such as chalkiness, excessive thinness, or physical damage.
Reason
Driven by feedback from global pearl industry stakeholders, the GIA has revised its methodology. The new approach introduces a five-tier scale for nacre evaluation: Excellent, Very Good, Good, Fair, and Poor. This more nuanced system aims to enhance transparency and create better consistency with how other pearl value factors are graded.
Standard details
Extensive research, which included a wide range of pearl specimens with diverse surface and sub-surface features, forms the basis of this updated nacre scale. The objective was to more accurately represent the variety in nacre development and consistency observed during a pearl’s formation. It is anticipated that under this new framework, the “Good” rating will become the most common designation, effectively replacing the former “Acceptable” grade.
Assessment of pearl items, including individual pearls, strands, and finished jewelry, will now incorporate visible nacre variations, conditions resulting from post-harvest handling (like wear or treatments), and established industry benchmarks for nacre thickness. The GIA report will reflect the nacre quality determined by these combined factors.
Evaluation
Tom Moses, GIA Executive Vice President and Chief Laboratory and Research Officer, stated, “Nacre is integral to a pearl’s character, influencing its luster, shape, and even its structural soundness. Our refined nacre classification scale will lead to a more precise and thorough evaluation, benefiting our clients and the wider trade.”
Summary
This enhancement underscores the GIA’s ongoing dedication to elevating gemological standards and maintaining its pearl reports as trusted, authoritative instruments for buyers, sellers, and collectors globally.
