Clarity Grading Diamonds
Clarity Grading Diamonds

Professional Gemologist Certification Course

Clarity Grading Diamonds

The Rise of the Four Cs Grading System

Until the mid 20th century, purchasing a diamond was very confusing. The grading terms dealers used, like “AA” and “AAA,” meant nothing to the average consumer. To make matters worse, even the definitions of these terms varied from dealer to dealer. Expert merchants fared little better. For example, they could wait months for an order of “AAA” clarity graded diamonds. On arrival, they might find the gems to be “AA” grade at best. They could either accept the order and offer lower grade gems to their customers or return the stones. Of course, this would mean more months of waiting and possible disputes. These conditions benefited no one.

To address this situation, various grading systems were introduced. However, each new system came with a new set of terms and definitions. Thus, they simply produced more confusion.

In 1953, the Gemological Institute of America (GIA) successfully introduced the now virtually universal diamond grading system. Their system is based on the Four Cs: carat, color, cut, and clarity. These standards now made it possible for dealers to have a good idea of a...


Donald Clark, CSM IMG

The late Donald Clark, CSM founded the International Gem Society in 1998. Donald started in the gem and jewelry industry in 1976. He received his formal gemology training from the Gemological Institute of America (GIA) and the American Society of Gemcutters (ASG). The letters “CSM” after his name stood for Certified Supreme Master Gemcutter, a designation of Wykoff’s ASG which has often been referred to as the doctorate of gem cutting. The American Society of Gemcutters only had 54 people reach this level. Along with dozens of articles for leading trade magazines, Donald authored the book “Modern Faceting, the Easy Way.”


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