Fodor's Expert Review Gassan Diamonds

By the beginning of the 18th century, Amsterdam had a virtual monopoly in the diamond industry in Europe, so when diamonds were discovered in South Africa in 1869, there was a windfall for Amsterdam's Jewish communities, a third of whom worked in the diamond trade. Built in 1879, Gassan Diamonds was once home to the Boas diamond-polishing factory, the largest in the world, where 357 diamond-polishing machines processed around 8,000–10,000 carats of rough diamonds per week. Today, Gassan offers polishing and grading demonstrations and free hour-long tours, in more than 27 languages, of the building and its glittering collection of diamonds and jewelry.