Our craftsman create the finest diamond jewelry for royals, celebrities, heads of state and young couples visiting Amsterdam. We have more than Diamond Engagement Rings · Royal Coster Watches · Education · Diamond Rings. Amsterdam has a long heritage of diamond trade and industry – the city has been a major diamond centre since Sephardic Jews introduced the. Free guided tour. For those who want to know all about carats, colors, clarity and cuts of diamonds, and also some of the history of this Amsterdam craft, visit.