China has been under the pressure from the US and other G-7 nations to halt its overseas support of coal power plants.

It also lowered its third-quarter sales outlook for contained zinc from its Red Dog operations in northwest Alaska.

New research shows that streams from heavily mined watersheds in the Appalachian mountains harbour 40% fewer species than streams with cleaner water.

US-based researchers are looking into the possibility of producing hydrogen fuel from hydrogen sulphide, also known as sewer gas.