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 will ...

A flawless blue topaz gemstone - the largest of its kind - will be displayed in the Museum's Minerals gallery from 19 October. The Ostro stone is the largest cut topaz to go on show at the Museum.

What makes the Whitney Flame topaz such an astonishing acquisition is its homogeneous fiery-red. “We recognized right away that this is something different than we’d ever seen,” says Smithsonian gems ...

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 ...

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 ...