Green Diamond

A diamond with a natural green body colour. Green must be the predominant colour, but it may be modified by shades of yellow or blue. The colour in natural green diamonds is created by exposure to natural irradiation in the earth that produces structural defects; natural green diamonds are extremely rare. Some green coloured diamonds with sufficient saturation fall into the valuable fancy green colour category of diamonds.

Graining

Faint wavy, hazy, oily, or distorted transparent and sometimes shadowlike lines, either inside the diamond or on the surface of a diamond. Graining is caused by irregular growth and crystallization that takes place when the diamond is formed. Also known as “growth lines.”

Grainer

Term used to describe a diamond weighing approximately 0.25 of a carat. In ancient times, 1.00 carat was equal to about four grains of rice. A “four grainer” would thus be referring to a diamond weighing approximately 1.00 carat (4 x 0.25=1.00).

Grading Report

A complete, accurate report describing the specific characteristics of a diamond, issued by a recognised and independent diamond grading laboratory. A diamond grading report lists all the characteristics of a diamond that allows you to determine its current appraisal and fair market value. Also called a Diamond Certificate. A diamond grading report is not an appraisal and does not contain a monetary value. Click here for a guide to the information that a diamond grading report must have.

Girdle

The outermost edge or rim of a diamond that outlines its shape. It is the circumference or perimeter that appears to divide the crown from the pavilion. A girdle may be faceted, polished, or bruted. The purpose of the girdle is to protect the diamond from damage such as chips.

Fracture Filling

Treatment to enhance the apparent clarity of a diamond, whereby a glass-like resin is injected into feathers or fractures that reach the surface of the diamond. Feathers are visible when light reflects off of them; by filling them with a resin, light is able to travel through the feather, making it less visible. The resin causes what is known as a flash effect in the treated diamond. Fracture filling is not a stable diamond treatment and is easily altered with heat; click here to learn more.