Definitions of Aggregate, Sand, Gravel, Crushed Gravel, Crushed stone, Rock, and Slag

AG AGGREGATE is made up of inert material such as sand and gravel, crushed stone or slag, which when bound together into a conglomerated mass by a matrix forms concretes, mortars, plaster and mastics such as black top or macadam roads and asphalt road surfaces.

SDSAND is a finer granular material (usually lass than 1/4″ in diameter) resulting from the natural disintegration of rock or from the crushing of friable sandstone rock or other suitable rocks.

GLGRAVEL is a coarse granular material (usually larger than 1/4″ in diameter) resulting from the natural erosion and disintegration of rock.

CGCRUSHED GRAVEL is the product resulting from the artificial crushing of gravel with most all fragments having at least one face resulting from fracture.

CSCRUSHED STONE is the product resulting from the artificial crushing of rocks, boulders or large cobblestones with the fragments having all faces resulting from the crushing operation.

RKROCK, from which crushed stone, sand and gravel are made and the rock most suitable for making good aggregates is formed all over the world. See physical properties table for the various kinds of rocks and their physical properties.

SLSLAG is the air-cooled, non-metallic by-product of a blast furnace operation consisting essentially of silicates and alumina-silicates of lime and other bases which is developed simultaneously with iron in a blast furnace. Naturally, it is only available in those localities where pig iron is produced.