GIA Gem Project
Beryl

Photo by Robert Weldon/GIA, courtesy Dr E. J. Gübelin Collection
GIA Collection 33007, 34281, 34289, 34815, 34290, 25919, 34270, 35274, 35253, 33058, 32698
Chemically pure beryl is colourless, but trace elements give rise to green, blue and pink/red colours. The most important variety is green emerald (coloured by chromium or vanadium), followed by blue aquamarine and yellow heliodor (both coloured by iron) and pink morganite (coloured by manganese). Some beryls fashioned as cabochons exhibit asterism (a star-shaped pattern of reflections) or chatoyancy (a “cat’s-eye” seen in reflected light).