World’s 50 biggest mining companies have shed $627 billion since hitting highs in March this year even as investors pile into the best performing sectors.
There were no immediate reports of any injuries or deaths from the latest dam wall collapse at the dormant diamond mine, which was once owned by De Beers.
More sanctions on individuals - including those involved in organizing Moscow's ad hoc votes in occupied east Ukraine on joining Russia - are also expected.
The collapse of a tailings dam in South Africa earlier this month has put the spotlight on the need for binding global regulations of facilities used to store mining waste.