AGGREGATE (from the Latin word "aggrego" which means "join" * EN: aggregate; DE: Gesteinsaggregat; FR: agregat; ES: agregado; RU: агрегат) is the combination of the mineral grains or their intergrowths, which are forming the rock or its part.

The aggregates may be simple, which are comprised of a single mineral (mono-mineral aggregates), and composite, which are comprised of the several different minerals (polymineral aggregates). For example, marble is the simple aggregate of calcite, and granite is the composite aggregate, which is comprised of the feldspars, quartz, and mica.