A blue topaz stone, thought to be the largest-ever, is to go on permanent loan to the Natural History Museum in London. It has been handed over by the family of gemstone pioneer Max Ostro, who ...

LONDON (Reuters) - A flawless blue topaz gemstone, said to be the largest of its kind, is set to go on display at London's Natural History Museum. The Ostro stone weighs around 2 kg (4.4 lb) and ...

THE WORLD'S biggest piece of cut blue topaz gemstone has been unveiled 30 years after it was discovered by a swashbuckling British adventurer likened to Indiana Jones. Max Ostro escaped death at ...

Smithsonian Museum of Natural History Receives Rare Red Topaz The gemstone is giant at nearly 49 carats By Zach Vallese • Published September 21, 2018 • Updated on September 21, 2018 at 4:29 pm ...

A blue topaz stone, thought to be the largest-ever, is to go on permanent loan to the Natural History Museum in London. It has been handed over by the family of gemstone pioneer Max Ostro, who ...