The Alfred's Barley Crusher MaltMill, the "Home Brewer's Best Friend" has proven to be just that. A high quality grain mill constructed using materials that will last a lifetime. 1018 cold rolled steel rollers on bearings with aluminum body and hopper.
A. Abutment - In coal mining, (1) the weight of the rocks above a narrow roadway is transferred to the solid coal along the sides, which act as abutments of the arch of strata spanning the roadway; and (2) the weight of the rocks over a longwall face is transferred to the front abutment, that is, the solid coal ahead of the face and the back abutment, that is, the settled packs behind the face.
INSTRUCTIONS: Work in groups of three. Choose one mining industry in South Africa and find information about the industry of your choice. Choose from the following list: gold, iron, coal, phosphate, manganese, diamond, chromium, copper and the platinum group metals (PGMs).