The Korloff Noir is one of the world's largest known black diamonds.
Before it was cut and polished, it had 421 carats.
It is named for the Korloff -Sapojnikoff family, members of the Russian nobility, who once owned it.
In 1978, Daniel Paillasseur, a French jeweller, purchased it.
[1] The Korloff Noir is currently owned by the Korloff Company, which was founded by Paillasseur.