Crushed Stone & Gravel Description & Uses (new
Crushed stone is produced by crushing quarry rock, boul ders, cobbles, or large size gravel. Crushed air cooled blast furnace slag is also used as fine or coarse aggregate. The aggregates are usually washed and graded at the pit or plant. Some variation in the type, quality, cleanli ness, grading, moisture content, and other properties is expected.Jun 03, 2019 Igneous rocks are those that form via the process of melting and cooling. If they erupt from volcanoes onto the surface as lava, they are called extrusive rocks.By contrast, Intrusive rocks are formed from magma that cools underground. If the intrusive rock cooled underground but near the surface, it is called subvolcanic or hypabyssal, and often has visible, but tiny mineral grains.