ZGL Laboratories Are Respected Diamond Grading Laboratory. We Have Pioneered The Development Of The First Scientific System Used To Evaluate How Well A Diamond Has Been Cut. A Diamond’s Cut Is The Most Important C Of All Of The Four C’s. When A Diamond Is Well Cut It Reflects And Refracts Light To The Maximum Degree. ZGL Has Been Acclaimed As A Worldwide Innovator Due To Our Extensive Research And Development In Determining The Cut Grade Of Diamonds.

Diamond grading is the process used to evaluate the true characteristics and therefore the true value of a diamond. ZGL’s diamond gradin process is well known for our unique eight-step process.

It is essential for each diamond proprietor to know the credentials of their diamond in order to obtain confidence and assurance of the integrity of what they have acquired. An ZGL Diamond or Gemstone Certificate is a statement issued by one of our independent gemological laboratories documenting the characteristics of the stone as determined by our experienced diamond graders at the time of evaluation.