以下是 GIA 将休业的法定假期列表。 2025 年 5 月 5 日（星期一） 玛哈•哇集拉隆功国王陛下加冕（补假） 2025 年 5 月 12 日（星期一） 卫塞节（补假） 2025 年 6 月 3 日（星期二） 王后陛下诞辰 2025 年 7 月 10 日（星期四） 守夏节 ...

GIA's legacy of rigorous standards, deep expertise, and advanced technology is now available for jewelry. Submit your item for a comprehensive, convenient Jewelry Report ...

Opal can range from 5 to 6.5 on the Mohs hardness scale. Hardness and toughness Gem and mineral hardness is measured on the Mohs scale. The numbers are based on the relative ease or difficulty with ...

A synthetic gem material is one that is made in a laboratory, but which shares virtually all chemical, optical, and physical characteristics of its natural mineral counterpart, though in some cases, ...

GIA studied more than 400 important gemstones from the Gübelin Collection and is committed to sharing this repository of gemological information. This work is a valuable resource for all students, ...

Established in 1931, the Gemological Institute of America (GIA) is the world’s foremost authority on diamonds, colored stones, and pearls. A public benefit, nonprofit institute, GIA is the leading ...

Diamond is the only gem made of a single element: It is typically about 99.95 percent carbon. The other 0.05 percent can include one or more trace elements, which are atoms that aren’t part of the ...

Sapphire is one of the big three of colored gemstones (the other two are ruby and emerald). This durable gemstone captures jewelry buyers with its practicality and aura of romance. Click here and ...

GIA Knowledge Sessions, a series of talks and seminars that promise to engage participants in the most diverse and pressing issues in gemology today, including gemstone origin, laboratory-grown stones ...

Attain your dreams of a GIA education with scholarships. We encourage on-campus students to apply for assistance and we are happy to help you coordinate your efforts. GIA-administered scholarships are ...

Amethyst, the February birthstone, is the purple variety of quartz. It is said to prevent drunkenness and make you quick witted in business. You once had to be rich to own this birthstone for February ...

The Graduate Jeweler diploma program is a hands-on experience that introduces students to the knowledge and skills required for a career in jewelry fabrication and repair. You will work with gemstones ...