Spinel is a crystal often mistaken for other gemstones, it was only officially recognised as a separate mineral around 150 years ago. Throughout history many famous rubies are actually Spinel, such as the Black Prince's ruby in the British Crown Jewels. One of the contributing factors to this confusion is the fact that it can be found alongside ruby and sapphires in deposits, especially the famous sapphire and ruby regions of Myanmar, Cambodia and Sri Lanka. Spinel can be found in many colours, from bright blues, to reds, pinks and even greens and blacks, and rarely forms in large crystals. Despite this, there are some exceptionally large crystals in existence, one of the largest ever found is the Samarian Spinel, weighing 500cs and measuring 5.5cm in size. According to legend it dates back to the 10th Century BC, and was used to adorn the Biblical Golden Calf, however it is now a part of the Iranian Crown Jewels.