Underground, at a depth of 1,000 ft (305m), is Birkshead drift mine where a lengthy system of conveyor belts snakes its way from where the stone is mined to where it is treated. "You've got to ...

“The connection drift development and test mining efforts have been very successful to date, which is a testament to our mine crews’ ability to operate safely and efficiently.

Eastern Pennsylvania is home to beautiful farmlands and countryside, but it's also a gold mine of information for ... is an extreme example of "genetic drift." Genes occurring at a certain ...