Diamond certificates are often referred to as the “5th C” to consider when purchasing either a vintage or contemporary wholesale diamond or diamond ring. The evaluator analyses the diamond for quality and maps out each diamond’s characteristics on the certificate. While dozens of companies provide this service, the two most respected and recognized by the jewellery industry include the Gemological Institute of America (GIA) and the European Gemological Laboratories (EGL).
Key Points of a Diamond Certificate
While certain companies may differ slightly in what they evaluate, diamond certifiers all check the 4 C’s: colour, clarity, cut, and carat size. You can tell if the certificate is authentic by checking for the serial number on it. At the top, you’ll also find key points like the date it was issued, the certificate number, the diamond shape or cut style such as Round Brilliant, and the measurements and dimensions of your stone.
The 4 C’s
The report begins by grading each of the 4 C’s. Evaluators often start with carat weight as it’s the easiest to determine and the one that buyers are most interested in. Simply put, one carat equals .2 grams.
Next, you’ll find the grade for your diamond’s colour on your report. Traditional white diamonds are evaluated on a grading scale from D-Z, with D to F, being white and colorless, and S through Z showing tints of yellow. Generally, G is the standard for white diamonds because it’s near colorless and affordable, though E and F are certainly better.
Graders examine your diamond under 10X magnification to check for flaws and imperfections before assigning a clarity grade. If your diamond is rated IF, it means it’s internally flawless with no marks or inclusions. However, as the grading system moves to VS or SI, it could feature very slight or slight imperfections.
Professionals must also evaluate your diamond’s cut as it affects all of the other diamond’s characteristics. If it was cut poorly, it can affect how well imperfections are hidden or how easily color shines as well as the proportions of the diamond. If the diamond is cut properly, the proportions and facets will work together to make your diamond shine brilliantly. A diamond cut is measured on a scale of excellent to poor.
Other Important Details on a Diamond Certificate
In addition to looking at the diamond cut, graders also determine the finish and the symmetry of the diamond, using the same excellent to poor sliding scale. They evaluate the finish to determine how well it’s polished to eliminate any scratches or graining, irregularities in the crystal structure. Then they grade the symmetry of the diamond, based on how evenly the facets were cut and how they are distributed so they light shimmers off of them.
Most reports also include pictures and charts, detailing the information related to your diamond’s proportions, an in-depth look at the clarity characteristics, and the grading scale they used. The diamond’s proportions feature the measurements and angles of a finished and polished diamond. If it’s done correctly, the information will show the proper dimensions for its carat weight. In fact, table size, crown angle, and pavilion depth have a great effect on your diamond’s appearance as correct proportions hide imperfections and show retracted light better.
If you’re looking to purchase certified antique or modern wholesale diamonds by Diamond Queensland or anywhere else, you should ensure that you have a certificate when you make the purchase. This will ensure you that your diamond is genuine, and you bought something of good value.