AGS Certification: History and Recent Developments

Last Updated on August 29, 2023 by Juli "Jewels" Church

Have you ever found yourself mesmerized by a sparkling diamond, wondering about its quality and authenticity? I know I have. In a world filled with dazzling gems, understanding what lies behind their brilliance is a complex but fascinating journey.

AGS certification

When it comes to gems, certification is a term we often hear but might not fully grasp. Let me explain. Certification, specifically through institutions like the American Gem Society (AGS), offers a detailed analysis of a gem's quality and characteristics. AGS certification, renowned for its rigorous standards, is a beacon of integrity in the jewelry industry. 

Why should we care about AGS certification? The answer is multifaceted, much like the gems themselves. For jewelers, AGS diamond certification enhances credibility. For consumers like you and me, it offers assurance, helping us to make informed purchasing decisions. It's a mark of quality, a symbol of trust, and a guide to the gem's true value.

In this blog post, I'll guide you through the multifaceted world of AGS certification. Together, we'll discover why AGS certification stands as a hallmark in the jewelry industry. By the end of this exploration, I hope you'll see gems not only as items of beauty but as treasures backed by science, ethics, and integrity. Shall we begin?

Background of American Gem Society

The American Gem Society was founded in 1934 with a mission that resonates even today: to protect the jewelry-buying public. Established by Robert M. Shipley, the society's formation was a response to the need for ethics and knowledge in the jewelry industry.

The purpose of AGS extends beyond simple certification. It's about setting a standard of excellence, a benchmark that reassures both jewelers and consumers alike. Its approach, rooted in education, professionalism, and consumer protection, sets it apart from others in the field. With an emphasis on integrity and ethics, AGS certification provides not just an analysis of a gem but a guarantee of its quality.


Membership within the American Gem Society is prestigious and signifies a commitment to ethical conduct. Members, including jewelers, suppliers, and designers, are held to high ethical standards, providing further assurance to consumers that they are engaging with professionals who value quality and ethics above all else.

GIA Takeover

In a remarkable development that marks a new chapter in the field of gemology, AGS and the Gemological Institute of America (GIA) have announced an advancement in their long-standing collaboration. This strategic move is aimed at pursuing innovation, serving the needs of today's jewelry professionals, and furthering consumer protection missions.

Strategic Collaboration and Endowment

GIA has created an endowment to support AGS and its membership through various educational initiatives. This collaborative effort will result in additional educational opportunities for members of both organizations, enhancing the overall knowledge base within the industry.

Integration of Research Efforts

In a bold move that leverages the unique strengths of both organizations, AGS and GIA have combined their gemological research efforts. By integrating AGS Laboratories' expertise, intellectual property, and technology, they aim to develop new GIA products and services that will not only protect consumers but also support the trade.

Closure of American Gem Society Laboratories

As part of this strategic decision, the American Gem Society has closed AGS Laboratories. This allows the Society to concentrate solely on advancing its mission, education, and membership programs. Meanwhile, the combined efforts of AGS and GIA teams will be channeled towards focusing on new products and services.

Impact and Future Prospects

This collaboration between AGS and GIA signifies a transformative moment in the world of gems and jewelry. By uniting their strengths and resources, they are poised to foster innovation, enhance education, and create new pathways to ensure the integrity of the trade and the protection of consumers.

The decision to join forces in this manner reflects a shared vision and commitment to excellence. It sets the stage for exciting developments in the field, promising to shape the future of gemology in ways that align with the evolving needs and expectations of both industry professionals and consumers.

This latest update on AGS Labs represents a pivotal milestone, reaffirming the roles of AGS and GIA as leading authorities and innovators in the gemological community. It's a collaboration that resonates with purpose and potential, and one that the entire industry will watch with anticipation and interest.

AGS Diamond Grading Reports: Past and Present

The American Gem Society (AGS) has played a pivotal role in shaping the diamond industry through its meticulous and detailed grading reports. Now, with a significant collaboration between AGS and GIA, the landscape has evolved, introducing a new report that reflects the innovative synergy between these two organizations.

Previous AGS Diamond Grading Reports

Criteria and Grading System

The AGS certification process revolves around the "Four Cs" — Cut, Color, Clarity, and Carat Weight, but with unique grading scales and additional factors:

  • Cut: AGS's diamond cut grading system ranges from 0 (Ideal) to 10, assessing factors like proportions, symmetry, and polish. It's a complex measure that requires a profound understanding of how light interacts with the gem.
  • Color: AGS uses a 0 to 10 scale, with 0 indicating a completely colorless diamond. The system evaluates the nuances of diamond color within the gem, a task that demands meticulous observation.
  • Clarity: The clarity scale also ranges from 0 to 10, with 0 representing a flawless gem. AGS's system carefully examines inclusions and blemishes, contributing to an accurate portrayal of the gem's internal and external characteristics.
  • Carat Weight: AGS provides precise measurements for the gem's size and weight, which are vital in determining its overall value.
4 Cs of Diamonds

The diamond grading system's accuracy and specificity reflect the AGS's commitment to providing comprehensive and understandable information about a gem's quality and beauty.

Diamond Quality Analysis

This AGS diamond report was a comprehensive document that offered precise details on a diamond's characteristics. It evaluated the gem according to the AGS's strict criteria, providing in-depth insights into its cut, color, clarity, and carat weight. This analysis was essential for both jewelers and consumers, offering a transparent and accurate representation of the diamond's quality.

Here's a sample report:

AGS Diamond Quality report

Platinum Light Performance Diamond Quality Document

This specialized report went beyond the basic evaluations to focus specifically on the diamond's light performance. By analyzing how a diamond interacts with light, the Platinum Light Performance Diamond Quality Document provided unique insights into its brilliance, fire, and sparkle. This detailed analysis allowed for a greater understanding of a diamond's aesthetic appeal, something that resonated with both industry professionals and diamond enthusiasts.

Here's what it looked like:

AGS platinum light performance diamond quality report

The Current AGS Diamond Grading Report: AGS Ideal® Report by GIA

With the collaborative efforts between AGS and GIA, a new digital-only report has been introduced: the AGS Ideal® Report by GIA.


The AGS Ideal® Report by GIA is available for eligible colorless natural and laboratory-grown round brilliant diamonds and fancy shaped diamonds. It may be requested with or without an AGS Laboratories computer-generated light performance map known as an Angular Spectrum Evaluation Tool® (ASET®).

AGS ideal report sample page 1

Comparison with GIA Grading

While a GIA diamond grading report emphasizes the traditional 4Cs, the AGS Ideal® Report by GIA focuses on a light performance grade by analyzing the diamond's ability to find light. This adds a layer of complexity and nuance to the evaluation process.

Unparalleled Light Performance

Offered as a supplement to any natural or laboratory-grown D-to-Z reports, the AGS Ideal® Report brought to you by GIA combines AGS's unparalleled Light Performance measurements with GIA's industry-leading diamond grading. The AGS Light Performance assesses the performance, proportions, and finish of a diamond. In a stone with an AGS Light Performance grade of 0, the diamond exhibits brightness from edge to center, high fire potential, and an equal amount of contrast scattered across the entirety of the stone, minimizing light leakage.

The evolution of AGS's diamond grading reports, culminating in the AGS Ideal® Report by GIA, exemplifies a commitment to innovation, precision, and collaboration within the gemological community. Whether assessing traditional aspects or delving into the unique light performance characteristics, these reports have consistently provided invaluable insights.

The latest collaboration between AGS and GIA has set a new benchmark in diamond grading, reflecting a forward-thinking approach that embraces both the scientific rigor and the artistry of gemology.

Impact of GIA and AGS Diamond Grading

In the landscape of diamond certification, two institutions stand as pillars: the Gemological Institute of America (GIA) and the American Gem Society (AGS). Their influence and contributions to diamond grading have reshaped the industry in profound ways.

Setting Global Standards

GIA's introduction of the 4Cs (Cut, Color, Clarity, and Carat Weight) has become the universal language for evaluating diamonds. AGS's emphasis on light performance and rigorous grading scales complements this standard, adding depth and nuance to the evaluation process.

Pioneering Research and Innovation

Both AGS and GIA have been at the forefront of gemological research and innovation. Their combined efforts, such as the recent collaboration leading to the AGS Ideal® Report by GIA, highlight a commitment to advancing knowledge, developing new products, and protecting consumers.

Enhancing Consumer Confidence

GIA and AGS's grading reports are revered for their accuracy, consistency, and integrity. This reputation fosters consumer confidence, ensuring that buyers can trust the information presented to them. Their educational initiatives also empower consumers to make informed decisions.

Ethical Practices

A commitment to ethics and responsible practices is at the core of both AGS and GIA. Their certifications often include information about a diamond's origin and adherence to ethical standards, strengthening the bond of trust between the industry and its customers.

Influence on Other Certifying Bodies

The methodologies and standards set by GIA and AGS act as benchmarks for other certifying bodies. Their influence extends globally, shaping practices and expectations across various certification institutions.

Comparing AGS Diamond Certification with Other Certifications

In the realm of gemology, certification plays a crucial role in establishing trust, transparency, and accuracy. While AGS has been a renowned leader in this field, there are other certifying institutions that also contribute to the industry's integrity. Below, we'll explore how AGS diamond grading approach stands apart from how other institutions grade diamonds.

The AGS diamond grading processes have been a hallmark of quality and precision. From their meticulous grading scales to their unique focus on light performance, AGS's standards have set them apart. Their recent collaborative efforts have only furthered their mission to provide the best in diamond certification.

AGS vs EGL (European Gemological Laboratory)

While AGS has placed a strong emphasis on scientific rigor and uniform grading scales, EGL's approach has sometimes been considered more flexible. Some consumers and industry professionals may find variations in grading between different EGL labs. AGS's consistency and adherence to strict standards provide a benchmark that some find more reliable.

AGS vs IGI (International Gemological Institute)

IGI is another global player known for its diamond certification. While IGI's widespread presence and accessibility have made it a popular choice, AGS's commitment to ethical practices, research, and innovation has created a distinctive reputation for quality. AGS's focus on education and consumer protection aligns closely with their overall mission, setting them apart.

AGS vs HRD Antwerp

HRD Antwerp, a European certification body, is known for its quality assurance in diamond grading. Like AGS, HRD has shown a commitment to rigorous scientific analysis. However, AGS's emphasis on light performance and consumer education adds unique dimensions to their certification process that distinguish them from others.

The Importance of Diamond Certification

Diamond certification is more than just a document; it's a declaration of quality, authenticity, and value. It plays a central role in the diamond industry, acting as a bridge between scientific analysis and consumer trust. Let's explore why diamond certification is so essential.

Authenticity and Trust

A diamond graded confirms that the stone has been examined by professional gemologists using specialized tools and techniques. This impartial evaluation authenticates the diamond's characteristics and ensures that what is being presented to you is genuine. For consumers, this creates a foundation of trust in both the product and the seller.

Detailed Analysis of Quality

Certification goes beyond mere authentication. It delves into an in-depth analysis of the diamond's attributes, including the 4Cs: cut, color, clarity, and carat weight. It might also include assessments of light performance, proportions, and finish, providing a comprehensive picture of the stone's quality. These details are instrumental for consumers and jewelers alike, allowing for informed decisions and accurate pricing.

Ethical Assurance

In today's world, ethical sourcing and responsible practices are paramount. Some diamond certifications include information about the diamond's origin and whether it complies with ethical standards. This assurance aligns with the values of many consumers, who seek not only beauty and quality but also peace of mind that their purchase supports responsible mining and trading.

Comparison and Value

Diamond certification enables comparison between stones, ensuring that you are comparing "apples to apples." By providing standardized information on a diamond's attributes, certification allows for an accurate comparison, be it for purchase, investment, or appraisal. It establishes a transparent value system that underpins the trade at every level, from wholesale to retail.

Resale and Legacy

A diamond's certification accompanies it throughout its journey, preserving its story and its value. Should you ever decide to resell the diamond, the certification provides the next owner with all the necessary details, maintaining its worth and legacy. It's a document that carries the weight of history, science, and artistry, encapsulating the essence of the diamond.

FAQs on AGS Diamond Certification

What is the difference between natural and laboratory-grown diamonds in AGS grading?

Both AGS and GIA apply similar rigorous standards to both natural and laboratory-grown diamonds. The key difference lies in the origin, and the grading report will specify whether the diamond is natural or lab-grown. The AGS Ideal® Report by GIA also extends to eligible colorless laboratory-grown diamonds.

How do I verify an AGS or GIA grading report?

Both AGS and GIA offer online verification tools. By entering the report number into the respective institution's website, you can access the digital version of the grading report, ensuring its authenticity and accuracy.

Can a diamond's grade change over time?

While the intrinsic characteristics of a diamond remain stable, external factors such as wear and tear or damage can affect its appearance and thus its grading. Regular maintenance and proper care can help preserve the diamond's original grade.

What if a diamond has certifications from multiple labs?

It's not uncommon for a diamond to have certifications from different labs. However, due to variations in grading methodologies, the reports might differ slightly. It's advisable to refer to reputable institutions like AGS and GIA for the most accurate and consistent grading.

How does the AGS Light Performance grading work?

AGS's Light Performance grading evaluates a diamond's ability to interact with light. Factors like brightness, fire potential, and contrast are analyzed. The AGS Ideal® Report by GIA integrates this unique light performance grading, providing an insightful assessment of the diamond's visual beauty.

Is certification important for colored gemstones as well?

Yes, certification is equally vital for colored gemstones. It provides information about the gemstone's origin, treatments, color, clarity, and more. AGS, GIA, and other reputable labs offer certifications for colored gemstones.

Sparkling Perspectives: A Closing Insight

Navigating the multifaceted world of diamond certification can be as dazzling as the gems themselves. Whether you're a jeweler, collector, or someone making a heartfelt purchase, understanding the significance of certifications, especially those provided by esteemed bodies like AGS and GIA, can transform your experience.

Embrace the wisdom encapsulated in these intricate grading systems, explore the beauty revealed through light performance, and engage with the ethical practices that resonate with your values. Remember, behind every diamond's sparkle lies a universe of science, art, and human endeavor, and it's a journey worth embarking on with confidence and curiosity.

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