The blue-colored gemstone has a six-pointed star-shaped reflection or distinctive mark in the center.
This very large star sapphire was discovered in Ratnapura (known by the nickname "City of Gems"), in southern Sri Lanka, in August 2015. It was named "The Star of Adam" by the current owner, as a reference to Muslim beliefs that Adam arrived in Sri Lanka and lived on Adam's Peak after leaving the Garden of Eden.
The owner of the gem, preferring anonymity, told the BBC World Service's Newsday radio programme that "The moment I saw it, I decided to buy", and added "this was not a piece of jewellery but an exhibition piece".
The blue star sapphire's weight of 1,404.49 carats (280.898 g; 9.9084 oz) was certified by the Gemmological Institute of Colombo; the institute said that it had never certified a gemstone larger than "The Star of Adam". A leading gem and jewelry dealer in the country confirmed to the BBC that it was the largest blue star sapphire in the world.
In an interview to BBC Earth, Simon Redfern, mineral scientist from the University of Cambridge, said "the stone could have formed within the granite rocks of Sri Lanka's highlands. It was able to grow so big because of constant but slow change in temperatures and pressures within the rocks for millions of years".
Later, the gemstone was valued at over $300 million.