The Schatzkammer, or Imperial Treasury, is part of the Hapsburg Palace complex (adjoining the Swiss Court) in central Vienna. Here you'll find the Crown jewels and other fascinating treasures of Austria (including an alleged unicorn horn -- probably actually from a sperm whale). One of the most prized items in this collection is the Imperial Crown of the Holy Roman Empire , also known as Reichskrone.
This crown is very historic, having been worn by kings of the German Empire since the Middle Ages. While its precise history is not known, it's thought to have been crafted during the late 10th or early 11th centuries. Unlike modern crowns which have a rounded shape, this one is octagonal although its edges are rounded off on top. Each plate of the crown is made out of 22 carat gold giving it a rich yellow "buttery" color. Over 280 pearls and semiprecious stones (including emeralds, sapphires, and amethysts) have been incorporated into it, inlaid such they help reflect light. Note that none of the stones are faceted Decorative plates in the crown have a Biblical theme.
And to think this is just one of hundreds of exhibits in the Schatzkammer! A very worthwhile stop while visiting Vienna.