Diamonds are considered valuable because of their strength, beauty and rarity.  Although used throughout manufacturing in drill bits and other tools, the mention of the word “diamond” usually brings to mind diamond jewelry.  Diamonds have been used for at least 2,500 years.  Diamonds in engagement rings date back to the 15th century.  Today, diamonds for jewelry are priced according to the gemological characteristics known as the four c’s: carat, clarity, color and cut.

Carat And Clarity

The carat shows the weight of the diamond.  The price for a diamond jumps at each milestone carat weight so that the value of a 1.7 carat diamond is much less than that of a 2.2 carat diamond because demand for a diamond is usually measured by the carat weight.  Total carat weight is the total weight of all diamonds in a piece of diamond jewelry.

Clarity measures the inclusions or defects of a diamond. Inclusions can be cracks or foreign materials, whether they can be seen by the naked eye or not.  Only 20 percent of all diamonds are graded with a clarity level high enough to make them gem stones.  The other 80 percent are industrial diamonds. A diamond that has imperfections that can’t be seen without a loupe is referred to as “eye-clean.”  The grading of clarity depends on the number, size, color, location, orientation and visibility of the inclusions.

Color And Cut

A true diamond without inclusions that affect color is white or colorless.  Color in a diamond is caused by imperfections and are usually yellow or brown.  Color is graded from colorless or “D” to bright yellow or “Z.”  The colorless diamonds are more valuable for diamond jewelry, although the bright yellow color is rare enough to be valuable, too.  Diamonds can also have varying degrees of pink, blue, or green.  Diamonds that are noticeably colored are very valuable.  Pink and blue diamonds are sought after for diamond jewelry.

The most common cut for a jewelry diamond is the round brilliant with 57 facets or polished faces.  Cutting has been developed for hundreds of years with great strides made by Marcel Tolkowsky, a mathematician and gemologist.  Cuts other than the round brilliant are called “fancy cuts.”  Popular cuts are the baguette, marquise, princess, heart, briolette and pear.  Only the round brilliant cut has very precise measurements that must be adhered to.  The value attached to cuts is usually determined by fashion.  During the art deco period the baguette cut was popular.  It emphasizes the diamond’s luster while downplaying its fire.  The princess or square cut is gaining popularity currently.  Since it wastes the least amount of rough diamond compared to other cuts, it is popular among diamond cutters, too.

The four C’s determine the value of a diamond, but not necessarily the beauty.  When shopping for diamond jewelry, buy with your heart and not with your head.