A 30-carat rough diamond is viewed at the offices of a polishing factory in Antwerp

A 30-carat rough diamond is viewed at the offices of a polishing factory in Antwerp

A 30-carat rough diamond is viewed at the offices of a polishing factory in Antwerp, Belgium, April 28, 2016. Reuters/Francois Lenoir

March 12, 2017 9:36 PM (UTC+8)