The name "spinel" is probably derived from the Latin word "spinella", itself derived from the Greek work meaning "spark", probably in reference to the bright red or orange color of some crystals. Spinel comes in a wide variety of beautiful colors and is especially prized for its red, blue, pink, and purple varieties. The red variety has oftentimes been mistaken for ruby, and many of the so-called "rubies" in Europe's crown jewels are actually spinel. A faceted red spinel of more than 400 carats belonged to Empress Catherine II of Russia, and is now part of the Russian Treasure in the Kremlin.