Tradition says Pedro the Cruel took the "Black Prince's Ruby" from a Granadan sultan he killed with his own lance; it is a spinel in the front of Britain's crown

The stone called the Black Prince's Ruby is a red spinel of about 170 carats, not a ruby. Muhammad VI of Granada, known to the Castilians as Abu Said, fled to Seville in April 1362 with most of Granada's royal treasury. At Tablada, Peter I of Castile struck him with a lance, and 36 of his men were killed. The chronicler Pero López de Ayala wrote that the treasure was the main reason for the murder. Tradition says Peter took the spinel from the dead sultan^†. In 1366 and 1367 Edward the Black Prince fought for Peter, who could not pay him. Tradition says Peter gave him the stone instead. That link was first suggested in the 1760s and is disputed. English records of 1377 list balas rubies from Spanish treasure. Henry V is said to have worn the stone at Agincourt in 1415^†. A great balas ruby appears in Henry VIII's crown in a 1521 inventory. The Commonwealth broke up the crown jewels after 1649. In 1661 a large ruby was bought back for £400, possibly this stone. In 1838 it was set in the front of Queen Victoria's Imperial State Crown. It is in the Imperial State Crown in the Tower of London.