GIA Redefines Laboratory-Grown Diamond Grading: What You Need to Know
By
Tiffany Moore , Tuesday, October 07, 2025
The Gemological Institute of America (GIA) — the world’s foremost authority on diamond grading — has announced a significant change in how it evaluates D-to-Z laboratory-grown diamonds which took effect on October 1, 2025. This update marks a pivotal shift away from the traditional
4Cs grading system (Color, Clarity, Cut, and Carat) used for natural diamonds.
Instead, GIA will introduce a simplified, descriptive approach that classifies lab-grown diamonds as either Premium or Standard based on their overall quality and craftsmanship. This new framework reflects the Institute’s recognition that most lab-grown diamonds occupy a relatively narrow range of quality characteristics, and therefore benefit from a more streamlined assessment method.
By adopting this new structure, GIA underscores an important distinction: lab-grown diamonds are a product of highly controlled manufacturing, whereas natural gemstones formed over billions of years within the Earth with color and clarity grades representing rarity factors. For consumers, this change provides a clearer understanding of how laboratory-grown diamonds are evaluated and reinforces the separation between synthetic and natural diamond categories in the modern jewelry market.
Key Changes to GIA’s Evaluation Approach
As of October 1, 2025, GIA has officially implemented a revised framework for assessing D-to-Z laboratory-grown diamonds, marking a fundamental change in how quality is described and communicated. Under this new system, GIA no longer applies the traditional 4Cs grading terminology—the established standard used for natural diamonds—in evaluating lab-grown stones.
In place of the familiar color and clarity grades, GIA now uses two descriptive classifications—
Premium and
Standard—to convey overall diamond quality. These designations reflect a combined evaluation of
color,
clarity,
cut,
polish, and
symmetry, providing a simplified yet comprehensive picture of each diamond’s overall quality and craftsmanship.
GIA President and CEO Pritesh Patel explained that this approach better reflects the realities of the lab-grown diamond market, where “most fall into a very narrow range of color and clarity.” By streamlining terminology, GIA aims to make its assessments more relevant to consumers while emphasizing the essential difference between natural diamonds formed in the Earth and lab-grown diamonds produced in a controlled environment.
This updated evaluation model accomplishes two key objectives:
- Improved consumer understanding – The simplified categories allow buyers to easily compare lab-grown diamonds based on broad quality distinctions rather than complex grading scales.
- Clearer product differentiation – By removing the natural diamond nomenclature, GIA reinforces that lab-grown diamonds are manufactured products with their own evaluative standards, distinct from the natural diamond grading system.
In essence, GIA’s revised methodology establishes a more transparent, product-specific framework for lab-grown diamonds—one that both aligns with their unique characteristics and preserves the integrity of natural diamond grading.
LAB GROWN DIAMONDS
1.00 D VVS2 Round Ideal
Precision Lab Diamond
$1,150
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1.01 D VVS2 Round Ideal
Precision Lab Diamond
$1,165
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1.02 D VVS1 Round Ideal
Precision Lab Diamond
$1,295
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1.02 D VVS2 Round Ideal
Precision Lab Diamond
$1,175
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Defining “Premium” and “Standard”
GIA’s new laboratory-grown diamond evaluation replaces individual 4Cs grades with two descriptive tiers that reflect an overall quality judgment. A diamond either qualifies as Premium, Standard, or not eligible for assessment (if it fails to meet the minimum thresholds below).
Qualification Criteria
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Designation
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Clarity
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Color
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Cut Grade (round brilliant only)
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Polish
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Symmetry
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Premium
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VVS and higher
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D
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Excellent
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Excellent
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Excellent
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Standard
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VS
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E–J
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Very Good
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Very Good
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Very Good(Good for fancy shapes)
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Important notes and nuances
- Round vs. fancy shapes: The cut grade requirement applies only to round brilliants. For fancy shapes, GIA evaluates finish (polish/symmetry), with symmetry permitted at Good for Standard.
- Color stringency: Premium is exclusive to D-color stones; Standard spans E through J.
- Holistic thresholding: To earn a designation, a diamond must meet all criteria for that tier. Falling short on any single parameter disqualifies the stone from that category.
- Non-qualifiers: Diamonds that do not meet at least the Standard minimums do not receive a GIA assessment.
Identification & documentation
- Every assessed laboratory-grown diamond is laser-inscribed on the girdle with “Laboratory-Grown” and a unique GIA quality assessment number.
- A printed assessment document accompanies each qualifying stone, summarizing its designation and evaluation details.
Cost and Submission Details
Alongside the new evaluation structure, GIA has introduced a streamlined pricing model and updated submission requirements for laboratory-grown diamonds. These adjustments are designed to make the assessment process more accessible while maintaining GIA’s rigorous identification and documentation standards.
Fees and Minimums
- Assessment Fee: US $15 per carat, with a minimum charge of US $15 per stone.
- Evaluation Fee (Non-qualifying Stones): Submissions that do not meet the minimum criteria for a Standard designation incur a US $5 evaluation fee instead of the full assessment charge.
- Minimum Submission Size: Only diamonds weighing 0.15 carats or larger are eligible for evaluation.
This pricing structure offers transparency and consistency, ensuring that laboratories, retailers, and consumers can anticipate costs regardless of stone size or final designation.
Inscription and Documentation
Every qualifying laboratory-grown diamond receives:
- A laser inscription on the girdle reading “Laboratory-Grown”, accompanied by the unique GIA quality assessment number for traceability and verification.
- A printed GIA Laboratory-Grown Diamond Quality Assessment document, which clearly indicates the diamond’s classification (Premium or Standard) along with essential quality observations.
This documentation (which is now referred to as a Quality Assessment instead of a Report) replaces the traditional GIA grading report format used for natural diamonds, reinforcing the Institute’s commitment to maintaining a separate and transparent framework for evaluating laboratory-grown products. The combination of inscription and printed record ensures each diamond’s authenticity and classification can be independently verified, providing confidence for both consumers and the trade.
What This Means for Consumers
GIA’s adoption of the Premium and Standard classifications represents a strategic shift in how laboratory-grown diamonds are evaluated — one that affects not only jewelers and manufacturers, but also how consumers interpret diamond quality.
For decades, buyers have relied on the
4Cs framework — Color, Clarity, Cut, and Carat Weight — as the universal language of diamond quality. By moving away from that model for lab-grown diamonds,
GIA is signaling a deliberate distinction between
natural diamonds and laboratory-grown counterparts.
Simplified Understanding for Buyers
The new descriptive system is designed to make quality interpretation easier for consumers. Rather than navigating a complex range of letter and number grades, buyers can now quickly understand whether a laboratory-grown diamond meets GIA’s stringent Premium or Standard criteria. This approach emphasizes overall quality rather than isolated technical grades.
Reinforcing the Distinction Between Diamond Types
By removing the 4Cs nomenclature from its lab-grown diamond documentation, GIA highlights that these stones are manufactured products, distinct in origin and formation from natural diamonds. This differentiation helps maintain clarity in the marketplace and prevents the conflation of natural and synthetic diamond categories — a growing concern as lab-grown options become more common and visually equivalent to their natural counterparts.
Comparison with Other Laboratories
While GIA has taken a bold step toward redefining lab-grown diamond evaluation, most other major gemological institutions have not followed suit — at least for now. An exception is HRD which will no longer be accepting lab grown diamonds for evaluation.
This divergence means that, for the time being, lab-grown diamond reports from different labs may look quite different. Consumers comparing stones graded by GIA versus IGI or GCAL should pay close attention to the terminology used and the evaluation system behind it.
Implications for the Market
In the near term, GIA’s simplified system may bring greater shopping ease and consumer confidence to the lab-grown diamond sector, particularly for those seeking straightforward, descriptive quality tiers. Over time, it may also encourage a broader industry-wide conversation about how synthetic diamonds should be represented — as a separate product category with distinct standards rather than a derivative of natural diamond grading.
Ultimately, this change reinforces the value of education and transparency in diamond buying. Understanding how each laboratory defines and measures quality is essential for making informed comparisons, whether choosing a precision-crafted natural diamond or a premium quality lab-grown stone.
The Whiteflash Perspective
At Whiteflash, our philosophy has always centered on
education, transparency, and precision — guiding customers through the diamond selection process with clear, factual information. GIA’s new approach to laboratory-grown diamond evaluation reinforces many of these same principles by providing a distinction in how diamond types are presented to consumers, and a simpler framework for quality determination.
While this new Premium and Standard framework simplifies the assessment of lab-grown diamonds, it also reinforces a fundamental truth: natural and laboratory-grown diamonds are not the same product.
Natural diamonds are geological rarities — formed over billions of years deep within the Earth — whereas laboratory-grown diamonds are produced in controlled conditions within weeks. Both share essentially the same chemical composition, but their origins, rarity, and long-term market value are distinctly different.
Whiteflash welcomes GIA’s commitment to accurate labeling and differentiation, as it supports our own dedication to integrity and informed choice. Customers deserve to understand exactly what they are purchasing, and GIA’s move toward descriptive categories helps remove ambiguity in the marketplace.
3 Prong Martini Diamond Earrings
However, for buyers who prioritize cut precision, optical performance, and craftsmanship, detailed light performance analytics — such as those provided through
Whiteflash Precision Lab diamond standards — remain the benchmark for true visual excellence. While GIA’s system simplifies quality descriptions for lab-grown diamonds, cut quality and performance imaging continue to be the defining factors in a diamond’s beauty and brilliance, whether natural or lab-created.
At Whiteflash, we continue to offer both natural and laboratory-grown diamonds, each backed by comprehensive certification and advanced light performance imaging. Our goal is to ensure that every customer, regardless of choice, has access to transparent, high-quality information that supports confidence and understanding in their purchase.
Conclusion
GIA’s new laboratory-grown diamond evaluation system marks a significant evolution in diamond grading philosophy, acknowledging the rapid growth and maturing of the lab-grown sector. By replacing the traditional 4Cs with simple and logical descriptive categories, GIA has created a framework tailored to the nature of laboratory-grown diamonds — one that simplifies communication and underscores the distinction between natural and synthetic origins.
For consumers, the shift offers greater ease and accessibility, allowing them to make confident, informed choices based on very specific quality tiers. For the industry, it represents a defining moment that may influence how other laboratories and retailers position laboratory-grown diamonds in the future.
As the landscape continues to evolve, Whiteflash remains committed to providing unbiased education, precision craftsmanship, and transparent analysis— empowering customers to navigate these changes with complete confidence. Whether selecting a naturally formed masterpiece or a laboratory-grown alternative, the focus remains the same: exceptional beauty, exceptional quality, and an exceptional shopping experience.