This is fresh or unhardened concrete that is placed into suitable moulds in the position in which it will be used. For larger jobs it can be purchased from a local ready mixed concrete supplier whose name can be found in Yellow Pages or similar directories. For small jobs the separate ingredients may be purchased from a local builders merchant. For small volumes of concrete builders merchants often sell pre-batched dry mixes, containing the separate ingredients in the right proportions. Alternatively, for larger volumes, the ingredients can be purchased separately from the builders merchants. Whether pre-packed or purchased separately the ingredients can be either hand or machine mixed on the job.
The basic materials of concrete are cement, aggregate and water. Other materials can be incorporated to modify the properties of the fresh or hardened concrete. These include admixtures, pigments, fibres, polymers and reinforcement.