Backed by decades of research and the examination of thousands of colored diamonds, the GIA Colored Diamond Grading System has become the standard for evaluating these extremely rare gems. Current GIA ...

Established in 1931, the Gemological Institute of America (GIA) is the world’s foremost authority on diamonds, colored stones, and pearls ... Through research, education, and unbiased gem grading and ...

Muscle strength grading is used to categorize muscle strength on a scale of 0 to 5 in relation to the expected strength for a muscle. One of the more common methods is a hands-on test called the ...