Although the 1980s did not experience the emergence of several totally new synthetics that characterized the preceding decade, it was during this period that synthetics matured, with many new ...

Scientific advances in the past decade have completely altered our understanding of certain concepts relating to the age and origin of diamonds. As a generalization, most diamonds formed more than 990 ...

长久以来，镶工和金工必须不断改良自己的工具，才能在镶工工作台上完成不同的工作。 镶工不可或缺的工具就是锤子。 如今，镶工可使用各种形状和材料的锤子。 这里举例说明了如何改良锤子用于铆接、塑形、成型以及调整戒指尺寸。 锤子一头为圆形或 ...

GIA is proud to provide the most comprehensive research in the industry with a world-renowned field gemology team and a dedication to acquiring colored stones directly from the source. Our ...

Advances in technology and increased demand for lower-priced gem materials contributed to the proliferation of new treatments throughout the first decade of the 2000s. The developments that made the ...

Figure 1. Pleochroism in a 15 ct tanzanite, as seen with the unaided eye through the crown and the pavilion sides and ends. Photo by Wimon Manorotkul. In describing colored gemstones, the major ...

A relatively new production of red corundum, reportedly from Bangkok, has been offered for sale in recent years. Although the producers claimed that these stones were red diffusion-treated corundum (i ...

This is the second part in a three-part series on the origin of color in gem materials. This article discusses colors produced by (1) processes that involve multiple atoms (e.g., blue sapphire, ...

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 ...

搜索城市或邮政编码，查找出售 GIA 分级钻石或有经过 GIA 培训的员工的零售商。搜索结果包括地址、营业时间和路线。 “查找零售商”列表上显示的营业时间可能不准确。建议联系各家商店，确认目前的营业时间。

GIAでグレードされたダイヤモンドのを取り扱う、またはGIAにより訓練を受けたスタッフのいる小売業者を、都市名またはや郵便番号で検索します。検索結果には住所と営業時間、そしてアクセスの仕方が記載されます。 小売業者検索リストに記載された営業 ...

3.28カラットのパライバ産トルマリンの、この鮮やかなバイオレットがかった青の色相は、最高級のサファイアに匹敵する。 このトルマリンの希少性から、1カラットあたりの価格もまた、高級なサファイアの価格に匹敵する可能性がある。 色 トルマリンの ...