图 1：含有一种称作铁方镁石深色内含物的含硼蓝色钻石，作为此项研究的一部分进行了检测。这颗宝石重 0.03 克拉。摄影：Evan M. Smith（埃文·M.·史密斯）。 这是《自然》杂志中发表的文章 ...
GIAに宝石をご提出いただく場合は、ラボサービスアカウントを開設していただく必要があります。アカウントはすべてオンラインで簡単に開設していただけます。 アカウントを開設するため ...
The People's Republic of China has recently placed a high priority on identifying and developing its gemstone resources. Initial exploration by teams of geologists throughout China has identified many ...
Surface-treated topaz has become a viable alternative to topaz colored by irradiation. Unlike irradiation, which modifies the entire gemstone, coloration by chemical modification is limited to the ...
Synthetic diamond growth was first documented in 1952 by William Eversole of the Union Carbide Corporation, but it took another two decades before GIA issued the first grading report for a ...
The September birthstone is sapphire – a gem that’s been cherished for thousands of years. Although the term sapphire usually refers to the blue variety of corundum (ruby is the red variety), this ...
The Chinese have labored to perfect the art of gemstone carving for several thousand years. Beginning with primitive tools and limited materials, they eventually developed the iron-tipped spindles and ...
Demantoid, green andradite garnet, was discovered in the Central Ural Mountains of Russia in the mid-19th century. A favorite of the Czar's court, demantoid was another victim of the 1917 Bolshevik ...
瑞々しい青、鮮やかなバイオレット、濃い紫色のバランスを整えたエキゾチックなタンザナイトが発見される場所は、地球上でただ一つ、雄大なキリマンジャロ山の近くにあります。
何世紀もの間、アフガニスタンは最高品質のラピスラズリの重要な産出地です。 歴史家は、人間とラピスラズリの間のリンクが6,500以上さかのぼると信じています。 宝石はメソポタミア ...
東南アジアで最も活気に満ちた都市の一つ、およびカラーストーンの世界最大の取引中心地の一つとされているバンコクにあるGIAは、ラボラトリーや教育サービスにとって極めて重要です。
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