tiara

thumb|Tiara made for the French princess Marie-Thérèse, Duchess of Angoulême, 1820

A tiara (, ) is a head ornament adorned with jewels. Its origins date back to ancient Persia, from where it was later popularized by the Greco-Roman world. By the 18th century, the tiara had become fashionable in Europe as prestigious pieces of jewelry worn by women on formal occasions. The basic shape of the modern tiara is a semicircular base, usually made of gold, silver, or platinum, and richly decorated with gemstones, pearls, or cameos.