G.D.S. International S.r.l.
Gaedtke Robin
Galey Thomas
Garrison, Jr. Joseph R.
Gem Optical Co., Ltd.
Gemological Institute of America (GIA)
Gengler Peter
Gerlach Dianne S.
Geurts Ron
GIA Gem Institute Corporation
Gingerella Sherman
Girard Edouard
Glick Louis
Goepfert Juergen R.
Goff James A.
Gordon Kerry W.
Gottfried Philip H.
Grabes Oliver Felix
Grace Timothy
Grau Werner E.