Mean from 4 samples (Mitchell et al. 2001)

Limestone is a sedimentary carbonate rock, composed primariily of calcium carbonate (CaCO3) alongside impurities such as clay, sand and iron,

Most limestones are hard and durable, and their primary use by volume is the production of construction aggregates.

Heated above around 750ºC, calcium carbonate (CaCO3) decomposes to calcium oxide (CaO) and carbon dioxide (CO2). This reaction is relied upon as the basis of the manufacture of cement, lime and in many glass and ceramic compositions. The release of CO2 through this decomposition is a major contributor to industrial emissions.

Limestone quarry wastes typically show high consistency and are one of the few fine-particled mineral wastes to have an established market, used as a filler in asphalt, or for aglime, a mineral fertiliser (Manning and Vetterlein, 2004).