During the depths of the Depression, a middle-aged man with little more than ambition and charisma revolutionized the gem and jewelry industry. Robert M. Shipley established the Gemological Institute ...

Ruby is the July birthstone – and it’s one of the most coveted of gems. The name is derived from the Latin word ruber, meaning “red” – the color of love and passion. Few things catch the eye like the ...

モルガナイトの歴史、研究、品質係数等をGIA Gem Encyclopedia（GIA 宝石百科事典）で詳しく調べる。