World's biggest star blue sapphire set to go on sale

A Sri Lankan displays a star blue sapphire, claimed to be the worlds biggest star blue sapphire on his palm in Colombo, Sri Lanka, Friday, Jan. 8, 2016. Gemological institute of Colombo, a local gem industry body has certified that the gem weighs 1,404.49 carats (281 grams). (AP /Eranga Jayawardena)

COLOMBO, Sri Lanka -- A Sri Lankan gem merchant claiming to have the world's biggest star blue sapphire is ready to sell the precious stone he says is worth at least $300 million.

The Gemological Institute of Colombo certified the gem as weighing 1404.49 carats. The institute's chief gemologist Ashan Amarasinghe said according to the available data, the stone could be the biggest of its type.

The oval-shaped gem is as large as a man's palm and was mined from a gem pit near the central town of Ratnapura known as the "gem city" of Sri Lanka.

The present owner says he bought the sapphire last September from a local gem merchant and got it certified from the GIC. The owner spoke to the AP at his home in the capital Colombo but asked for his identity to not to revealed because he fears that he might be abducted or killed for the stone.

The institute's certification report says the stone is a "large specimen of unheated Blue Star Sapphire with a well-defined Asterism (star effect)."

The owner said the stone was brought to him cut and polished and he knew it was rare because of the size and the star on it.

He said he is willing to sell it, for the right price. The owner previously tagged a price of $100 million. But he said its fame has raised its value and he hopes it would be sold for around $300 million. He's already had offers but hasn't accepted any.

The owner said he named the stone "Star of Adam" because local legend says Sri Lanka's world-famous blue sapphires were formed by the tears of Adam after God expelled him from Paradise.

According to senior gemologists the previous three largest blue sapphires have all been found Sri Lanka. The National Gem and Jewelry Authority said the stone that was previously the largest star blue sapphire weighs 1,395 carats.

Sri Lanka's blue sapphires, also referred to as Ceylon sapphires, are renowned for their unique colour, clarity and shimmer in their cornflower blue lustre. They have been acknowledged as superior to sapphires sourced from other countries and have been collected by world royalty, wealthy collectors and museums.