Carat weight, or mass, is just one of many gemstone properties measured at GIA (box A). Measurements of physical dimensions and facet angles of polished gemstones, assessment of color and ...

Pursue your passion Whether you’re taking the next step in your professional journey or starting a new career, GIA courses and diploma programs prepare you for success. We offer the finest gem and ...

宝石学 宝石や高級宝飾品の美しさと科学の魅力を存分にご堪能ください。 ジュエリー 刺激的な小売業の世界で上手に接客するために宝石や宝飾品に関する知識を習得します。 デザイン あなたの創造性を発揮し、生活にあなたの宝石類のインスピレーションをもたらすための技術を習得します。

Examination of samples of faceted "Ocean green" topaz reveals that this material has been irradiated in a nuclear reactor. An earlier reactor-irradiation experiment suggests that temperature ...

Consumers now, more than ever, have a heightened awareness of sustainably and ethically sourced products. The GIA Diamond Origin Report uses scientific evaluation to provide confirmation of a ...

Results from spectroscopic analyses of GE POL high-pressure high-temperature (HPHT) annealed nominally type IIa diamonds are presented, and these spectral characteristics are compared with those of ...

Gems & Gemology, the professional quarterly of GIA, debuted in 1934. Appearing in the 306 th issue, this article looks back at the first 75 years. By reviewing the journal’s milestones, it also traces ...

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 ...

The June Hong Kong Jewellery & Gem Fair opens on June 22, a mid-year trading event for the gem and jewelry trade. Visit GIA at booth 3M100. Learn about sales tools, aids and apps available through the ...

GIAについて 1931年設立の独立非営利組織であるGIA（Gemological Institute of America）は、宝石学における世界有数の権威として認められています。GIAはカラー、クラリティ、カット、カラット ウェイトからなる有名な4Cを考案し、さらに1953年にはダイヤモンドの品質の基準として世界中で認知されて ...

其中包括 Marie-Thérèse粉钻戒指以及超过 30 件其他珍贵珠宝 加利福尼亚州卡尔斯巴德– 2025 年 6 月 12 日 – 6 月 17 日纽约举行的佳士得“Magnificent Jewels”拍卖会之前， GIA美国宝石研究院 已对超过 30 件稀有且具有历史意义的珠宝进行了鉴定。其中最引人注目的是 "Marie-Thérèse Pink粉钻" ，一颗 10.38 ...

CARLSBAD, Calif. – June 20, 2025 – The Board of Governors of the Gemological Institute of America, Inc. (GIA) has named Pritesh Patel, currently GIA’s Chief Operating Officer, as the Institute’s ...