DIAMOND TERMS GLOSSARY

Sell Diamonds in the United States
  • GaugeTool used to take the measurements of a diamond. Typically done in millimeters
  • Gemological Institute of America (GIA)Non-profit educational institution established in 1931 to serve the jewelry industry and the public. Their headquarters are in Santa Monica, California. The diamond grading reports which they issue are completely accurate and considered the standard of the industry
  • Gemological MicroscopeMicroscope specifically designed to examine gemstones
  • GemologistA specialist in gem materials who has successfully completed a recognized study in gemology
  • GemologyThe study of gemstones
  • Gem QualityDescriptive term used within the industry to describe a rough gem which has suitable qualities to be used in jewelry
  • GemstoneMineral or organic material which has sufficient beauty, rarity and reliability to be used in jewelry
  • GirdleNarrow band which circumscribes the plane separating the crown and pavilion of a polished diamond
  • Girdle DiameterDistance from one edge of the girdle on a polished round diamond to the point directly opposite on the other side
  • GlassyIndustry term for a polished diamond which lacks brilliance. Typically the result of a poor cut
  • GradingThe process of determining a diamonds color, cut, clarity, finish and proportions
  • Grain CenterSmall area of concentrated crystal distortion in a diamond. Usually associated with pinpoint inclusions
  • Grain LinesVisible, shadowy lines on the surface or inside of a diamonds caused by irregularities in its crystal structure
  • GrindingThe process of shaping the initial facets on a rough diamond