Diamond Certificate: Classification and How to Read It
Key Takeaways
- Diamond grading reports are certificates issued by reputable gemological institutes like GIA (USA) to verify the quality and value of a diamond. This is the most important legal basis for clarifying technical...
Diamond grading reports are certificates issued by reputable gemological institutes like GIA (USA) to verify the quality and value of a diamond. This is the most important legal basis for clarifying technical specifications and ensuring the rights of the owner regarding the diamond.
This diamond certificate provides accurate data based on the 4Cs standard (Weight, Color, Clarity, Cut). To understand the differences between GIA, IGI, or domestic grading reports, please follow the detailed content below with Jemmia Diamond.
Key Takeaway
- Grading reports are "birth certificates" authenticating the actual quality and value of a diamond.
- GIA certificates have the highest credibility and global liquidity.
- Grading reports provide objective data on the 4Cs (Cut, Color, Clarity, Carat) for valuation.
- Grading reports help buyers avoid counterfeit risks and facilitate exchanges and transfers.
- Diamonds of 3.6mm or larger usually come with a full grading report.
What is a Diamond Grading Report?
A Diamond Certificate is a detailed report on the quality of the stone, issued by reputable international gemological organizations such as GIA (Gemological Institute of America), IGI, or HRD.
This type of diamond grading report provides complete information on quality and important parameters such as: color, size, shape, and clarity of the diamond (diamond 4Cs standard).
Diamond grading reports are issued by reputable gemological and diamond appraisal centers
Currently, there are two common types of diamond grading reports: domestic and international:
- Domestic grading reports include: PNJ, GIV, and SJC.
- International grading reports are provided by leading appraisal centers worldwide: GIA, IGI, EGL, AGSL, HDR, etc., among which GIA grading reports (Gemological Institute of America) are the most valuable. This is a non-profit organization founded in 1931, specializing in appraising the quality of diamonds, gemstones, pearls, and fine jewelry.
In commerce, diamonds with international grading certificates are more expensive than those with domestic certificates. However, domestic appraisal centers also provide diamond grading with accuracy comparable to international organizations.
Types of International Diamond Grading Reports
GIA Diamond Grading Report
GIA grading reports are considered among the most reputable diamond grading reports today. GIA grading reports are issued by the Gemological Institute of America. It is a non-profit organization dedicated to research and evaluation of diamond and gemstone quality. With its independence and professionalism, GIA ensures the accuracy and objectivity of its appraisal reports.
The main content of a GIA grading report focuses on the unique characteristics and qualities of each diamond. This forms the basis for buyers and sellers to determine value.
GIA has developed a comprehensive 4Cs diamond valuation system. All laboratories operate under a unified principle and process. Currently, the GIA diamond certificate database system is used to store measurements and qualities of gemstones.
GIA is considered one of the most reputable diamond grading reports today
Each diamond is assigned a unique GIA report number. This number is usually found at the beginning of the report. The certificate displays the key elements for diamond valuation, including: carat weight, clarity, color grade, and cut.
See also: What is 8 Carat Natural Diamond Worth? Where to Buy Reliably?
Additionally, you can find supplementary information such as: finish, polish, symmetry, diamond fluorescence, proportion diagrams, etc. In the "Other Comments" section, you will find all other information related to the diamond displayed here.
AGS Diamond Grading Report
AGS grading reports are also commonly used for diamond quality assessment. AGS was founded in 1934 as the American Gem Society in the USA. The organization's purpose is to protect consumers from deception and fraud in diamond transactions.
In 1966, AGS successfully developed a diamond cut grading system. With its transparent standard appraisal process and professional expertise, AGS has become one of the diamond grading reports with high accuracy and reliability.
The value of each diamond is assessed by AGS based on quality factors and composition. Diamonds are categorized by different shapes: Round, Emerald, Princess, Oval, etc.
AGS was founded in 1934 as the American Gem Society in the USA
The appraisal report also analyzes diamond quality based on 4 factors: color grade, clarity, cut, and carat weight. Additionally, you will find other information about: Light performance, polish, symmetry, etc.
The biggest difference between GIA and AGS diamond grading reports is the grading system for cut quality. On the AGS scale, cut quality is ranked from 0 to 10, where 0 is a perfect cut and it decreases to 10 (poor quality cut). On the GIA scale, cut quality is classified as: Excellent, Very Good, Good, Fair, and Poor.
IGI Diamond Grading Report
IGI diamond grading reports are diamond certificates issued by the International Gemological Institute, founded in Belgium in 1975. The organization is committed to maintaining the highest standards of integrity in the appraisal of diamonds and gemstones.
IGI uses a numerical grading system to quantify the color, clarity, and cut of diamonds. On a scale of 0-10, 0 represents the most valuable diamond and 10 represents the least quality diamond. Each score corresponds to a value level based on the GIA diamond grading scale (which is globally accepted).
IGI Diamond Certification is a diamond certificate issued by the International Gemological Institute
IGI's diamond appraisal standards include:
- Weight: measured to the third decimal place using a digital carat scale.
- Clarity: determined under magnification with professional lighting, with clarity characteristics plotted on a diamond diagram.
- Color: graded by comparing it to pre-determined master stones.
- Finish: the finish of a diamond includes: polish, symmetry, and proportions.
IGI provides two types of diamond grading reports, including:
- IGI Diamond Report: this report details the specific characteristics of the diamond.
- IGI Diamond ID: this is a passport-sized document containing the same detailed information as the diamond report, without a diagram.
IGI diamond grading reports are reputable certificates, providing comprehensive analysis of the key factors of a diamond. Owning an IGI certificate helps prove the origin and quality of the diamond, and facilitates the buying and selling process.
Types of Domestic Diamond Grading Reports
When buying and selling diamonds in Vietnam, in addition to international diamond grading reports, customers will also encounter some domestic grading reports. There are 3 well-known diamond appraisal units currently: PNJ, GIV, and SJC.
See more: How Much is a 4.8mm Diamond Currently?
However, in terms of accuracy and credibility, domestic certificates are hard to match with GIA or AGS. But in terms of financial aspects and convenience, you can consider these appraisal organizations.
Domestic diamond grading report
If you are wondering where to buy quality diamonds, Jemmia is the perfect choice for you. The company always provides 100% unused diamonds with full documentation. To ensure customer rights, Jemmia's jewelry products are sold at very reasonable prices.
How to Read a Diamond Grading Report
In this article, we will learn how to read the grading report from the Gemological Institute of America (GIA), which is the most reliable laboratory in terms of diamond industry grading standards.
GIA offers two main reports: the Diamond Grading Report and the Diamond Dossier.
The Diamond Grading Report includes the 4Cs standard – cut, clarity, carat weight, and color, as well as dimensions, exact shape, and an inclusions plot of the diamond.
How to read a diamond grading report
- 1: Name of the laboratory issuing the report
- 2: Characteristics of the diamond
GIA Report Number: GIA diamond certificate number, which can be stored and looked up at: https://www.gia.edu
Shape and Cutting Style: diamond shape and cut style.
Measurements: dimensions of the diamond, accurate to the millimeter.
- 3: 4C Grading Results
See also: What is a Natural Diamond? Its Meaning and Value?
Carat Weight: diamond's carat weight.
Color grade: diamond color is graded from D to Z, with colors beyond Z being fancy colored diamonds.
Clarity grade: clarity is determined under 10x magnification.
Cut grade: refers to the cut grade of the diamond.
- 4: Additional Information
Polish: refers to the polish, indicating how smooth the diamond's surface is. Good polish can create sharp and undistorted light reflection.
Symmetry: is a comparison of the facets and their shaping.
Fluorescence: describes the level of glow when exposed to UV (ultraviolet) light.
Inscription: indicates the laser inscription number on the girdle of the diamond.
- 5: Proportion Diagram showing the cut: percentage of table, depth, angle, and girdle thickness.
- 6: Clarity Reference Chart: depicts internal inclusions and external blemishes.
- 7: Grading Scale: Cut, Color, Clarity shown through grade charts.
- 8: Security Features: Security marks such as tri-fold images, embossed seals, or product codes.
Diamond Dossier: Provides information similar to the grading report but without a diagram. It includes the laser inscription number on the diamond's girdle for authentication. This report is applicable only to diamonds weighing 0.15 – 0.19 carats.
What Size Diamonds Come with a Grading Report?
In practice, diamonds of approximately 3.6mm or larger (equivalent to ~0.25 carats) can be issued a grading report by reputable organizations such as GIA, IGI, HRD, etc.
Diamonds with grading reports are from 3.6mm upwards
How Important is a Diamond Grading Report?
A grading report is one of the most crucial factors in buying and owning a diamond. Even experienced individuals can face the risk of being tricked into buying a fake diamond if there is no grading report.
Specifically, it relates to the value of a diamond and must be carefully appraised to be recognized. Customers can now have diamonds appraised at appraisal centers nationwide to ensure quality and get more information about the professional assessment of the diamond if they intend to buy.
Diamond grading reports are very important in diamond trading
FAQ - Frequently Asked Questions about Diamond Grading Reports
Can a lost original GIA report be reissued?
A lost original GIA report can be reissued by sending the diamond to GIA laboratories for re-appraisal and a new certificate. Additionally, you can quickly look up information by entering the inscription number of the stone on GIA's official online archive system.
Are diamonds without a grading report fake?
A diamond without a grading report cannot be definitively classified as fake, but it makes it difficult to verify its actual quality and determine its accurate value. For safety, you should bring the stone to reputable centers like GIA or domestic gemological institutes for appraisal before making a transaction.
Should I buy diamonds with only domestic grading reports?
You can absolutely buy diamonds with domestic grading reports to save costs if you trust the appraisal unit. However, for high-value diamonds or investment purposes, prioritizing international grading reports like GIA will help ensure the best global liquidity and transfer value.
A diamond grading report is not just a simple parameter sheet, but the highest legal guarantee to determine the true value and protect the economic rights of the owner. Choosing diamonds with certificates from reputable organizations like GIA will give you complete peace of mind regarding transparency, natural quality, and the ability to maintain asset value sustainably over time.
See more: Diamond Grading Report: Classification and How to Read It
Do women's diamond rings require a grading report?
Yes. For beautiful women's diamond ring models with a center stone of approximately 3.6mm (0.25 carat) or larger, buyers should prioritize products with GIA or other reputable organization grading reports to accurately verify the diamond's quality, and to facilitate future valuation, exchange, or transfer.
We hope the information above has given you a comprehensive understanding and more confidence when choosing your gemstone. If you are looking for a perfect diamond with full international certificates and expert consultation, do not hesitate to contact the specialists at Jemmia Diamond for dedicated support.
