Diamond is The Ultimate Symbol of Love. So, what exactly is a diamond, anyway? A diamond is actually an extremely hard, usually clear type of crystalline carbon which is formed over millions of years. The process begins up to 120 miles beneath the earth’s surface when, with the right conditions, carbon atoms in melting rocks bond together to form diamond gemstones.
The loose diamond certification process is an easy way to boost buyers’ confidence during the shopping process. When diamond certification is conducted by a reputable organization, such as the Gemological Institute of America (GIA), buyers can rest assured that the diamond is a genuine, natural diamond, rather than grown in the lab as a synthetic diamond. It also reveals whether or not a loose diamond has been treated.
Traditionally, the overall quality and value of a diamond is reflected in four characteristics, known as the 4 Cs: Color, Clarity, Cut and Carat Weight.
Diamonds are available in a variety of hues, from rare, completely clear diamonds, to those which have an obvious yellow or brown tint.
Diamond color is rated on a scale from D (colorless) to Z (obviously yellow or brownish). Unless you are a diamond expert you will probably not be able to tell the difference between diamonds which are color graded D-I unless you are comparing diamonds side by side. Diamonds with higher color grades are rare and often command a premium price. However, color is largely a matter of personal preference and while some seek a near colorless diamond, others prefer a trace of color.
Certified diamonds classified as “D” are colorless, while those graded “Z” are light yellow or brown. Since truly colorless diamonds are extremely rare, the majority of diamonds used in jewelry are designated as “H” or “I” and have a slightly yellow tint—described by gemologists as “nearly colorless”.
Natural diamonds are formed under considerable heat and pressure, almost all diamonds have some internal inclusions (imperfections) or external blemishes. Most diamonds have flaws which cannot be seen except using 10x magnification. Diamonds which have no inclusions or blemishes are incredibly rare in nature. These flaws cannot be seen by the naked eye and do not affect the splendor of the diamond.
There are ten grades of diamond clarity, ranging from flawless (no inclusions visible under a magnifying glass) to I3 (inclusions visible to the naked eye).
Much like the human fingerprint, inclusions are markings that distinguish one loose diamond from the next. During certification, gemologists plot a diamond’s inclusions on a diagram to indicate its distinctive features—those that no other diamond has—which then get added to the certification paper. This diagram helps match each diamond to the proper certification, so buyers can be sure the diamond they’re evaluating is the same one on the report.
While people often think of cut as indicating the shape of a diamond (i.e. square or round), the term is used during certification to describe the stone’s sparkle and brilliance on a range from “Excellent” to “Poor”.
To assist with cut grading, gemologists place each loose diamond in a machine, rotating the stone 360 degrees and capturing every one of its facets to generate a sophisticated 3D model. Many factors are considered to determine the stone’s grade, including proportions, girdle thickness, culet size, polish, and symmetry.
Diamond Carat Weight
To determine carat size, certified diamonds are placed in high-tech, sealed-chamber electronic scales. The weights, which measure how close a diamond is to one carat (200 milligrams), round each stone to a second decimal place to arrive at a standard carat size measurement. As counter-intuitive as it might seem, bigger isn’t always better when it comes to diamonds. Value is determined by all four of the “C’s”, not just its weight.
Diamonds are weighed in diamond carat weights. A carat weighs 200 milligrams. Diamond professionals also use the point system for smaller diamonds, with 100 points being equal to one carat.
A carat is usually abbreviated to ct. Ct.tw. refers to total carat weight. It is the total weight of all the diamonds in a piece of jewelry. For example, in the case of diamond earrings, the total carat weight refers to the weight of the diamonds in both earrings together. If the total carat weight is 1 carat, each individual earring is set with a 1/2 carat diamond.
Diamond certificates, also known as diamond grading reports, are offered by independent gemological laboratories such as GIA (Gemological Institute of America) and EGL (European Gemological Institute). A gemology laboratory grades a particular loose diamond on various quality factors such as color, clarity, polish, symmetry and florescence. Certificates offer consumers an extra layer of confidence that the diamond is authentic and as described on the website. In most cases no mention is made about the value of the diamond.
Watch the video below, which chronicles one diamond’s certification journey at the Gemological Institute of America (GIA).