The 4 Cs of Diamond Quality

Beautiful. Rare. Cherished. Every diamond is unique and is a miracle of time, place and change. And each has specific qualities that establish its value. No two diamonds are exactly alike, they all share certain features that allow us to compare and evaluate them. These features are called the 4Cs.

No matter how beautiful a diamond may look you simply cannot see its true quality. Until the middle of the twentieth century, there was no agreed-upon standard by which diamonds quality could be judged. This is why over the years a universal standard for identifying diamonds has been set. GIA created the first, and now globally accepted standard for describing diamonds: the 4Cs and the International Diamond Grading System™. Today, the 4Cs of Diamond Quality is the universal method for assessing the quality of any diamond, anywhere in the world. It will provide you with the information you need to know the diamond’s actual quality, which will also help you understand the diamond’s value and price. 

The factors that define the 4Cs are Color, Clarity, Cut, and Carat.

  • Diamond Color refers to the absence of color. The less color in the stone, the more desirable and valuable it is. Some of these differences are not visible to the naked eye, but directly impact the overall quality and price of the stone. Grades range from ‘D ' to 'Z'.
  • Diamond Clarity measures the amount, size and placement of internal ‘inclusions,’ and external ‘blemishes.’ Grades range from ‘Flawless', with virtually no imperfections, to ‘Included', which contain a significant number of imperfections.
  • Diamond Cut does not refer to a diamond’s shape, but to the proportion and arrangement of its facets and the quality of workmanship. The amount of brilliance, sparkle, and fire in a diamond is determined by the cut. Grades range from ‘Excellent’ to ‘Poor'.
  • Diamond Carat refers to a diamond’s weight. Generally speaking, the higher the carat weight, the more expensive the stone. Two diamonds of equal carat weight, however, can have very different quality and price when the other three Cs are considered.
This short video explains the history of the 4Cs.