GCAL vs GIA Grading Reports

Buying a diamond starts with finding a trustworthy jeweler, but if you are planning to make a substantial purchase, you should ensure that the diamond has been graded by an accredited laboratory.
As far as the quality of a diamond is concerned, there is no other way to ensure it will be what the seller claims. It also allows shoppers to confidently compare their diamonds qualitatively with other diamonds available on the market.
Valoria Petite Pave Basket Diamond Engagement Ring
Valoria Petite Pave Basket Diamond Engagement Ring
Two of the most common acronyms you might see next to a diamond are The Gem Certification & Assurance Lab (GCAL) or the Gemological Institute of America (GIA). Through a comprehensive grading process, both the GCAL and GIA issue grading reports on diamonds, which involves evaluating the diamond's identifying characteristics, making qualitative judgements, and documenting the findings.
In the case of GCAL vs GIA Diamond certifications, which is better for your diamond?
The bottom line is that both labs have established excellent reputations for evaluating diamonds, despite their differences and functions in the market. Let's take a closer look at both, so that you can make an informed decision when it comes time to make a purchase.

Before we start:

A diamond's common attestation is called a 'certificate,' however, most laboratories do not provide such a document. They are better known as 'grading reports,' and they clearly state that grades are opinions.
Some may interpret the lab's certificate as an endorsement rather than a description of the diamond. Most people in the diamond trade still refer to diamond certificates, but some use the more accurate term grading report.
The GCAL is an exception, since it issues guaranteed certifications, however the extent of those guarantees is rather difficult to understand It is strongly recommended that you do not buy a diamond without a Grading Report.

What are GCAL Diamond Certifications?

GCAL Natural Diamond Certificate
GCAL Natural Round Diamond Certificate - Click to enlarge
As of 2001, The Gem Certification & Assurance Lab (GCAL) is headquartered at 580 Fifth Avenue in New York City, where it was founded by Donald Palmeiri.
GCAL provides a range of services for the gem and jewelry trade including grading and certification of natural diamonds, lab grown (synthetic) diamonds, diamond cut analysis, colored stone and pearl identification, precious metals analysis, as well as video and photography. Diamond jewelry reports and valuations are also available from GCAL.
Cut grading methodologies vary widely among labs, with some having no cut grade at all. The recent launch of GCAL's 8X® cut grade indicates that they are making a strong bid in this crucial area of diamond assessment.
According to GCAL, their new grading system encompasses all aspects of diamond cut quality assessment:
The lab is certified for ISO 17025, the highly respected international quality management system. ISO certification is an impressive thing for any business to achieve.

What are GIA Diamond Certifications?

The Gemological Institute of America (GIA)’s first laboratory opened in 1953 and the first diamond grading report was created. Over seventy years later, this grading system is still used by laboratories around the globe.
With few exceptions, the 4 C’s are still evaluated in the same way globally. In most labs, color and clarity grades are standardized. Some aspects of grading may differ between labs.
GIA Color Scale
GIA Color Scale
As far as gemstones and fine jewelry are concerned, no other organization has had as much influence as the GIA. For decades, the GIA has been grading diamonds using the same evaluation process. It involves:
The stone plot will also describe the internal and external characteristics of larger stones, at least those necessary to identify the stone and support its clarity grade. For high-end diamonds, GIA is also preferred.
GIA Certification
GIA Natural Round Diamond Certificate - Click to enlarge
In its earliest days, GIA was a pioneer of diamond grading instruments even teaching other jewelers how to use them. During the past few years, sophisticated devices have been developed to distinguish between natural and lab-grown diamonds.
The Gemological Institute of America has also recently combined forces with the American Gem Society (AGS) in the area of diamond cut research and development.
At present, GIA customers can order an AGS Ideal addendum report for diamonds that qualify for the AGS Light Performance grade of Ideal. AGS Ideal diamonds can be differentiated from the existing Excellent grade for rounds in this way if they meet both the GIA Ex cut standard and the higher AGS Ideal cut standard.
Additionally, GIA will now be able to issue cut grade reports for AGS Ideal cut fancy shapes, which will delight many brides-to-be looking for something a little bit different for their engagement ring.

GCAL vs GIA Diamond Certifications: How Do They Differ?

There are several rigorous protocols followed by both organizations to ensure accurate and reliable diamond certifications, but each organization has its own strengths in the market. The following is a summary of some of the differences.

Reputation and Recognition:

GCAL: GCAL is a small, high quality gemological laboratory with all operations in one location in the Diamond District of New York. They bring extensive experience and technical knowledge to providing a very wide range of services for diamonds, colored gemstones, pearls and fine jewelry. Their recent foray into comprehensive cut grading is indicative of their desire to remain on the leading edge of the industry.
While they primarily serve the diamond and jewelry trade, they've gained esteem over time as a trustworthy grading lab, establishing their own market presence alongside GIA's historical legacy.
GIA: The Gemological Institute of America is widely regarded as one of the most prestigious and internationally recognized diamond grading laboratories. It has been operating for since the early 20th century and is highly respected in the industry.
With a legacy spanning many decades, GIA has firmly established itself as not only a pioneer but also a paragon of credibility and integrity in the gem and jewelry industry. Renowned on a global scale, GIA's name is synonymous with the highest standards of gemological research, education, and grading.
Its contributions to shaping the gem and jewelry landscape are immeasurable, and its reputation as an expert remains unquestioned.


There can be a significant difference in the price of a diamond based on whether it has been graded by the GIA or GCAL.
A Diamond Grading Report itself does not include value or price. Only quality is reflected in grading reports, not pricing. Although market prices may change after the report is published, the report is intended to remain valid for a long time. For insurance purposes, an appraisal is the most reliable way to certify the value.
A diamond's personal value is derived from its enduring qualities, its capacity to capture hearts, and its ability to symbolize emotions that transcend generations. Embracing the journey alongside a seasoned jeweler undeniably plays a pivotal role in unearthing the inherent value within each diamond.
Even if we don't carry GCAL graded diamonds in our collection at Whiteflash, we are committed to excellence, ensuring that the diamonds we present are of the highest quality.


GCAL: Their expertise extends beyond diamonds to include colored gemstones, pearls, and fine jewelry. Situated in the Diamond District of New York, GCAL operates as a compact yet high-quality gemological laboratory, where all operations take place under one roof.
A jewelry appraisal conducted by GCAL can be tailored to suit the client's requirements. The GCAL can provide Retail Replacement Value for insurance purposes, Fair Market Value for charitable donations, or Marketable Cash Value for legal and personal settlements. GCAL offers identification as well as full grading reports on gemstones and pearls.
GIA: A wide range of gemology topics are studied by the GIA's staff of PhDs, scientists, and researchers. Over the years, thousands of specimens have been studied, which has led to the development of new services like Origin Reports - similar to GIA Diamond Grading Reports, but with a laser engraved report number and country of origin on the diamond's girdle.

GCAL vs GIA diamonds: Which Should You Choose?

Recognized as the premier grading authority, a GIA report is the most trusted report globally for the most important diamonds. However, both GIA and GCAL provide high-quality diamond grading services.
While GCAL's history might not stretch as far as some peers like GIA, their unwavering dedication to precision and integrity has gained them industry recognition. This holds true especially considering the rising popularity of lab-grown diamonds, where both GIA and GCAL play vital roles by screening and providing grading reports.
Both organizations provide clear, comprehensible analyses of diamond attributes to address this concern. Backed by a reputation for reliability, they deliver exceptional results not only for natural diamonds but also for lab-grown.
GCAL operates solely from its lab situated in the Diamond District of New York, while GIA has multiple locations. Moreover, GCAL employs its own grading system, distinct from that of GIA.
With the acquisition of AGSL by GIA, we have seen that the gem laboratory community is undergoing significant changes.
GIA's forte leans towards high-end diamonds, though there's a degree of overlap. Its name carries immense trust in the market due to its unparalleled reputation. In order to make an informed decision regarding a diamond purchase, you need to consider your specific needs, your budget, and the characteristics of the diamond you wish to purchase.
To summarize, both GIA and GCAL are highly reputable entities that offer top-tier diamond grading services. However, choosing between diamonds graded by them involves more than just the certificate or report itself. Among the factors that might influence your decision are the merchants expertise, the range of diamonds they offer, and other value added aspects of the overall purchase.
Delving into these factors can be complex, which is why seeking guidance from a seasoned expert becomes essential. Engaging with a knowledgeable jeweler like Whiteflash can provide invaluable insights and help you navigate these subtleties efficiently and effectively.
Reach out to a trusted professional who can guide you through the process so you can make an informed choice tailored to your preferences.

Not Sure Which Diamond Certification is Right for You?

As the diamond industry evolves, develops, and innovates, Whiteflash strives to stay ahead of it. We understand not everyone has the expertise we've cultivated over the years with our team and passion, so we encourage you to do your research.
You can take a look at our comprehensive diamond education resources on our website, or contact us directly for expert advice at your fingertips. Let us help you determine the best certifications for your needs, and the best diamond for your budget.

Be Inspired By Our Designer Engagement Rings

Find the perfect Designer Ring for your special diamond by clicking the links below, and let us build the ultimate ring for the love of your life!