About Diamond Weights

Diamonds are measured in Carat Weight. One carat weighs 200 milligrams. If a diamond is referred to as four grains, this also means that it is a one carat diamond. The word Carat comes from the word carob. A carob is a bean that grows on a tree in the Mediterranean. In times past, if a diamond weighed the same as a carob bean, it was one carob, or one carat.

However, in the far east, where Carob trees do not grow, rice was used to measure the weight of a diamond. If a diamond weighed as much as four grains of rice, it was four grains – or one carat as we know it to be now. The majority of diamond purchases are for diamonds that are 1/3 of a carat.

Beware when shopping for diamonds that are already set or mounted. If more than one diamond is used in the piece, the tag on the jewelry will give the CTW or Carat Total Weight – it does not tell you the carat weight of each stone in the piece. You need to ask the jeweler for the total carat weight of the largest diamond in the piece to truly understand what you are buying.

Selecting Diamonds

Diamonds are graded for certification by laboratories using grading criteria. Four of these criteria are critical to understand when making a diamond purchase or investment. Known as the “Four C’s” these criteria are: color, cut, clarity and carat.

Color is the result of the composition of a diamond and it does not change. When a jeweler is describing the color of a diamond they are referring to the presence or absence of color in white diamonds. Because a diamond with no color allows maximum light to pass through, colorless diamonds are preferred for their sparkle.

Cut refers to a diamonds reflective quality. Most diamonds are cut with 58 facets. The brilliance of diamonds is heavily dependent on the cut. The different angles and the finish of a diamond determine its ability to reflect light and cause its brilliance and fire. Remember that the cut of a diamond can have an impact on its durability as well as its beauty. Some cutting faults can make a diamond prone to breakage. A diamond that is cut too thin can also cause light to leak out of the back and the diamond will lose some of the sparkle and appear not to shine. So, as you can see the Cut is probably the most important of the Four C’s.

During the formation process, inner flaws, or inclusions occur in most diamonds. The number and size of these inclusions determine what is referred to as the clarity of a diamond. Diamonds that are clear create more brilliance and therefore are rarer and highly priced. To be considered
“flawless”, a diamond must have no surface or internal imperfections visible upon being viewed by a skilled diamond grader using 10 power magnifications.

Carat is the unit of weight by which diamonds are measured. One carat is equal to 200 milligrams. A carat is divided into 100 segments called points. 150 points would equal one and a half carats.

When you go to the store to make that all important diamond purchase, do not be shy! Ask questions, get the answers needed to make an informed purchase. Shopping for certified diamonds enables you to make an informed selection. Knowing the “four C’s” allows you to comparison shop and purchase the best diamond at a fair price. But, before making a purchase, shop around and decide what shapes and styles really appeal to you. Enjoy your diamond for years to come!