A rare 'Purple Star Sapphire' weighing a whopping 3,563 carats has been discovered in Sri Lanka. The stunning gem has been named the 'Star of Pure Land', and is believed to be the world's biggest natural star sapphire of its kind. Gemologists believe it could be worth at least $300million, making it one of the most valuable gemstones ever found. #gemstone #sapphire #srilanka #gem