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 ダイヤモンド オリジン レポート: 科学に基づくトレーサビリティ 消費者は、これまで以上に持続可能かつ倫理的に調達された製品に対する意識を高めています。 GIA ダイヤモンド オリジン レポートは、科学的評価を使用して、ダイヤモンドの地理的起源を確認します。 詳細（英語のみ） ...

The 75.47-carat Hooker Emerald was worn by Ottoman Sultan Abdul Hamid II, the last sultan of the Ottoman Empire. Photo by Chip Clark, courtesy Smithsonian Institution, National Museum of Natural ...

Figure 1. This 2.07 ct oval brilliant is the first faceted milarite examined by the Carlsbad lab. Photo by Diego Sanchez. Recently the Carlsbad lab received a light yellow 2.07 ct unknown gemstone ...

In November 2022, a parcel of 24 approximately 0.5–1.2 ct spinel crystals, described as cobalt-diffused, were obtained directly from a treater by the research team at GIA in Bangkok. Of these, seven ...

Diamonds have a long history as beautiful objects of desire. In the first century AD, the Roman naturalist Pliny stated: “Diamond is the most valuable, not only of precious stones, but of all things ...

GIA has been the starting point for many successful jewelry business owners, designers and jewelers. Our jewelry design and manufacturing programs offer you the opportunity to help you start a career ...

Graduate Jeweler Program 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 ...

Gemological LibraryResources The library provides a wide variety of gemstone-and-jewelry-related resources for students, staff, researchers, alumni, members of the industry, and the general public.

Search a city or postal code to find retailers who carry GIA-graded diamonds or have GIA-trained staff. Results will include addresses, store hours and directions. Store hours reflected on Retailer ...

Cultured pearls come in different sizes, shapes, and colors. Perhaps the best-loved gems of all time, pearls—both natural and modern cultured pearls—occur in a wide variety of colors. The most ...

In colored stones, transparency and clarity are closely linked. This is especially true for emeralds. The trade generally accepts eye-visible inclusions in higher-quality emeralds. But when the ...