The Koh-I-Noor is a 105-carat diamond. Almost certainly one of the most desirable gems on the planet, it has passed through the hands of many dynasties on the Indian subcontinent. There are some who believe the diamond to be the fabled Syamantaka Mani, perhaps the most famous jewel in Hindu mythology, supposed to be blessed with magical powers.
In 1850, the diamond was confiscated from the Sikh Empire by the British East India Company and became part of the British Crown Jewels when Queen Victoria was proclaimed Empress of India in 1877. The diamond is currently set into the Crown of Queen Elizabeth and is on display at the Tower of London.
It is believed that the Koh-i-Noor carries with it a curse which affects men who wear it, but not women. All the men who owned it have either lost their throne or had other misfortunes befall them. Queen Victoria is the first reigning monarch to have worn the gem. Since Victoria's reign, the stone has generally been worn by the Queen Consort, never by a male ruler.