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What is Diamond Certification?

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Why is Diamond Grading Important

A diamond certification guarantees the authenticity of the diamond. It confirms that the diamond is natural or a synthetic or treated stone. When you purchase a certified diamond, you can be confident that the diamond has been accurately represented. GIA's reputation for impartiality and accuracy makes its grading reports highly trusted in the diamond industry. Buyers can be confident in the quality and authenticity of GIA certified diamonds.

Certified diamonds come with a comprehensive report that details the diamond’s quality based on the 4Cs: Carat Weight, Cut, Color, and Clarity. This analysis allows you to understand exactly what you are purchasing and helps you compare diamonds more effectively.

A certified diamond’s value is based on its quality characteristics as documented in the certification. This transparency ensures that you are paying a fair price for the diamond, avoiding overpayment for subpar stones. The detailed information provided in a GIA report empowers consumers to make informed purchasing decisions, ensuring they get what they pay for.

Graded diamonds often command higher prices due to the rigorous and trusted nature of the certification. This certification can make a significant difference in the diamond's market value. Diamonds with certification tend to retain their value better and are easier to resell, as buyers are more confident in the diamond's graded characteristics.

A GIA/IGI diamond grading report provides a detailed description of these characteristics, along with other relevant information such as the diamond's fluorescence and measurements. This certification assures buyers of the diamond's quality and authenticity, making GIA graded diamonds highly trusted in the market.

How to Read a Diamond Certificate

Understanding how to read a diamond certificate is crucial for anyone interested in purchasing a diamond. A diamond certificate, also known as a diamond grading report, provides a comprehensive analysis of a diamond's characteristics and quality. These certificates are typically issued by independent gemological laboratories such as the Gemological Institute of America (GIA), the American Gem Society (AGS), or the International Gemological Institute (IGI). Here's a detailed guide on how to read and interpret the various components of a diamond certificate.

Certificate Number: Each certificate has a unique identification number. This number allows you to verify the report online on the issuing laboratory’s website.

Date of Issue: The date the certificate was issued. It’s important because the characteristics of a diamond can be re-evaluated if there is a significant time gap.

Shape and Cutting Style: Describes the shape of the diamond (e.g., round, princess, emerald) and its cutting style (e.g., brilliant, step cut).

Measurements: Indicates the diamond’s dimensions (length, width, and depth) in millimetres.

Colour Grade: Rates the diamond’s colour on a scale from D (colourless) to Z (light yellow or brown). The less colour, the higher the grade.

Clarity Grade: Measures the presence of internal or external imperfections. The scale ranges from Flawless (no inclusions or blemishes visible under 10x magnification) to Included (inclusions and/or blemishes visible to the naked eye).

Cut Grade: Assesses the quality of the diamond's cut, which affects its brilliance and sparkle. Grades can range from Excellent to Poor.

Carat Weight: This measures the diamond’s weight. One carat is equivalent to 200 milligrams. The carat weight affects the diamond’s price significantly.

Polish and Symmetry: Evaluates the diamond’s surface and the precision of its shape, respectively. Both are graded from Excellent to Poor.

Fluorescence: Indicates if the diamond glows under ultraviolet light and to what degree (None, Faint, Medium, Strong, Very Strong).

Inclusions and Blemishes: A diagram showing the type, number, and location of internal (inclusions) and external (blemishes) imperfections. This visual map helps in understanding the clarity grade

Table and Depth Percentage: These proportions affect the diamond’s brilliance. The table percentage is the width of the diamond’s top facet compared to its width, and the depth percentage is the total height compared to its width.

Crown Angle and Pavilion Depth: These angles and measurements influence how light travels through the diamond.

Girdle: The edge between the crown and the pavilion. It’s graded from Extremely Thin to Extremely Thick and can impact the diamond’s durability.

Culet: The small facet at the bottom of the diamond. Its size is rated from None to Large.

Some certificates note if the diamond has a laser inscription on the girdle. This can be the certificate number or a custom message, serving as an additional identification method.

This area may include additional remarks about the diamond’s characteristics or any treatments it has undergone (e.g., laser drilling, fracture filling).

Verify Authenticity: Always check the certificate number with the issuing lab's database.

Compare Diamonds: Use the certificate to compare diamonds of similar grades.

Consult with Experts: At Regal, our gemmologist can help you understand the details and implications of the certificate. 

Reading a diamond certificate requires understanding the terminology and grading standards used by gemmological laboratories. By familiarising yourself with these details, you can make an informed decision when purchasing a diamond, ensuring that you get the quality and characteristics you desire.