Many types of crushed stone: Crushed stone is not a "standardized commodity." It is made by mining one of several types of rock such as limestone, granite, trap rock, scoria, basalt, dolomite, or sandstone; crushing the rock; and then screening the crushed rock to sizes that are suitable for the intended end use.
The Romance of Steel A History of the Steel Industry by Herbert Newton Casson THE BIRTH OF THE BESSEMER PROCESS. On that bleak November day when Andrew Carnegie was born in a Scottish cottage, the iron and steel makers of America had no more thought of millions than of castles in Spain.
WHO WE ARE. Shanghai GBMachine Mining and Construction Machinery Co., Ltd. is a hi-tech, engineering group. We are specialized in the research, development, and production of industrial crushing, powder grinding, mineral processing equipments and other related devices.