Enhanced Diamond Gemological Laboratory

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E.D.G.L. is an independent Gemological Laboratory, which specializes in the
grading and analyzing of diamonds that have undergone Enhancing Treatments.

We issue Gemological Reports based on our highest professional opinion,
assessment, knowledge and wide experience in the specific field of

Our goal is to provide the consumer with a basic understanding of the
type of process that a diamond has undergone.

All diamonds certified by E.D.G.L. Laboratories bear a Laser Inscription on
the girdle, which is easy to locate with a magnifying glass. Thus, by comparing
with the E.D.G.L. Report Number, one can undoubtedly identify the diamond described.

Laser Drilled Diamond:
Laser Drilling is a process that is often used to remove dark inclusions and improve the diamond’s clarity. A tiny laser beam is used to drill into the diamond. Some inclusions are dissolved by corrosive acids that bleach the dark inclusions, but do not harm the diamond itself.
A newer type of laser enhancement, called KM, creates subtle cracks around inclusions near a diamond’s surface. The imperfection is removed by deep boiling and the remaining marks appear more like natural flaws than laser trails.

High Pressure High Temperature (HPHT):
HPHT is a process that converts low colored diamonds (usually M - O) into colorless/near colorless range (D - H). The treatment involves High Pressure and High Temperature. The HPHT technique has also been applied to yielding fancy yellowish green and greenish yellow colors, pink and blue colors.

Irradiation of diamonds using a nuclear reactor or linear accelerator, sometimes combined with heating, is used to produce a variety of different fancy colored diamonds.

Fracture Filling:
Fracture filling is a process for filling natural fractures in diamonds. Its purpose is to improve the clarity of the diamond by optically hiding the fracture. The fracture is filled with a non-permanent filler with optical qualities similar to those of a diamond. A Gemologist/Diamond Grader is able to identify the fracture filled diamond by looking for a flash of color, or “flash effect”. It is important to notify your jeweler that your diamond has been fracture filled before they begin any repair work on your piece.

A diamond Certificate from E.D.G.L. means that your diamond has been subjected to highly scientific evaluation, by a distinguished team of gemologists, using State-of-the-Art instrumentation and computer technology to assure you the most accurate assessment of the diamond that you are buying. Our laboratory environment and grading process is virtually impossible to duplicate anywhere else. When you are ready to buy a diamond, remember to ask your jeweler about the 5’Cs:

1. Color:
Colorless diamonds are extremely rare and highly valued. Most diamonds are nearly colorless with yellow or brown tints. The international grading system uses letters to represent colors, beginning with D (colorless) and ending at Z (light yellow or brown).

2. Clarity:
Most diamonds contain unique birthmarks called inclusions (internal) and blemishes (external). The international grading system grades the clarity range from Flawless diamonds, which contain no birthmarks to a diamond having major inclusions graded I-3.

3. Cut:
Describes the proportions, symmetry and finish of a diamond. It can also mean the shape of the stone as in Round Brilliant, Emerald Cut, Princess Cut etc.

4. Carat:
Diamonds are weighed using metric carats. A carat is divided into 100 points. 1 carat equals 0.20 gram.

5. Certificate:
Certificates identify and evaluate specific characteristics that determine the value of the diamond you select.
E.G.C. European Gemological Center Ltd.
8 Shoham St. Ramat-Gan 52521 Israel