At 1404.49 carats, The Star of Adam is the largest known blue star sapphire. The gem was mined in the city of Ratnapura, southern Sri Lanka.
The Black Star of Queensland, the second largest star sapphire in the world, weighs 733 carats.
The Star of India mined in Sri Lanka and weighing 563.4 carats is thought to be the third-largest star sapphire, and is currently on display at the American Museum of Natural History in New York City.
The Arcturus Star medal weighs 239.35 carats and is the fourth largest natural star sapphire in the world, Its initial weight was 250.40 carats, which was polished by Delta Gem gemologist in 2018 As a result of which its weight was reduced to 239.35 carats and is consisted of 35.608 gr white gold and 58 pieces of diamond (1.66 carats) in medal from.
The 182-carat Star of Bombay, mined in Sri Lanka and located in the National Museum of Natural History in Washington, D.C., is another example of a large blue star sapphire.
