Physical quality is defined as satisfactory, fair, or poor. Satisfactory aggregate has physical properties that make it suitable for most purposes. Fair aggregate has physical properties that make it useful for many purposes, but it commonly can not be used where engineering specifications are strict such as in concrete or asphalt. Poor aggregate has physical properties that greatly limit its use. In many circumstances, potential sources of crushed stone can be processed to improve its quality to meet special requirements.
Chemical quality is defined as either innocuous or deleterious.
Innocuous aggregate contains no constituents that dissolve or react chemically to a significant extent that the atmosphere, water, or hydrating portland cement while enclosed in concrete or mortar under ordinary conditions. Deleterious aggregate contains constituents in significant proportion which are known to react chemically under conditions ordinarily prevailing in portland cement concrete or mortar. The reaction may produce significant volume change, interfere with the normal course of hydration of portland cement, or produce other harmful effects upon concrete. How This Map Was Made The key to mapping potential sources of aggregate is an understanding of the geology of the region. Use of this Map Planners and other decision makers responsible for resource management should find this map useful in regional planning and land use management.