Also known as Carat Weight is the standard unit of weight used for gems.
Each carat (ct.) is equal to 0.200 grams (200 milligrams). Diamonds are weighed to 1/1000 of a carat (0.001) and rounded to the nearest 100th or point. Gems weighing more than 1 carat are usually expressed in carats and decimals. A 1.08 ct. stone would be described as “one point o eight carats” or “one o eight”. A diamond that weighs 0.74 ct. is said to weigh “seventy – four points” or a “seventy-four pointer.”
Most importantly, two diamonds can be of equal carat-weight, but their value can differ greatly due to their cut, color, and clarity.
TLDR | When someone refers to how many carats a diamond is, they are referring to it’s size or how big the diamond is.
A diamond color is measured from D (colorless) – Z (light yellow tint) color grade.
Beyond “Z” is the range where the diamond’s colour is vivid and rich, called “fancy colours” Natural Fancy Yellow Color Diamonds. Yellow diamonds exist in different tones from Light Yellow to Fancy Intense Vivid Yellow (also known as Canary Yellow).
Yellow diamonds are often more desirable than colorless diamonds, due to their warm yellow color. Inclusions in fancy diamonds are less noticeable to the eye because of the diamond’s rich color. The inclusions do not affect the look and sparkle of a diamond unlike their colorless counterparts.
Colored diamond grading system The following are terms used to describe natural yellow diamonds: Fancy Vivid Yellow – these diamonds are the most unique diamonds and are considered the rarest. Its very rich and vividly intense hue among all other ranges makes it the most expensive range of all fancy diamonds. Fancy Intense Yellow – this range of diamonds have richer color and quality. The value of this kind of diamond are higher compared to Fancy Yellow diamonds. Fancy Yellow – a lesser saturated yellow hue compared to the Fancy Intense Yellow diamonds which makes it a little cheaper compared to the other 2 ranges but still quite valuable. Light Fancy Yellow – a slight yellow tint that can be detected by human eye. Lighter shades are a great value because they still look yellow, yet you can have more size for your money.
Some diamonds can emit a visible light when exposed to ultraviolet radiation, this is called fluorescence. Fluorescence is not a factor in determining color or clarity grades of a diamond.
Diamond clarity is a measure of a diamond’s purity. Most diamonds contain very tiny impurities know as “inclusions.” A diamond’s clarity is determined by the number, nature, position, size and colour of internal characteristics called “inclusions” and surface features called “blemishes”.
Imperfections called inclusions or pique are measured from the highest grade:
Internally Flawless (IF),
Very Very Slightly Included (VVS1 or VVS2),
Very Slightly Included (VS1 or VS2),
Slightly Included (SI1 – SI3),
Included (I1 – I3), to the lowest grade.
Cut refers not to a diamond’s shape (e.g. round, oval, pear, etc.) but to a diamond’s proportions, symmetry and polish.
Diamond cut is perhaps the most important of the four Cs, so it is important to understand how this quality affects the properties and values of a diamond.
A good cut gives a diamond its brilliance, which is that brightness that seems to come from the very heart of a diamond. The angles and finish of any diamond are what determine its ability to handle light, which leads to brilliance. The cut of a diamond allows it to make the best use of light. When a diamond is cut correctly, light is reflected from one facet to another, then dispersed through the top of the stone. If the cut of the diamond is too deep, some light escapes through the opposite side of the pavilion. If the cut is too shallow, light escapes through the pavilion before it can be reflected.