20 mm metal refers to an aggregate material commonly used in construction and various applications. Stone has a maximum diameter or particle size of 20 millimeters (mm).
20mm metal stones are frequently used as a component in concrete mixtures to provide strength and stability. They are known as coarse aggregates in concrete.
Environmental considerations may include responsible sourcing of materials, minimizing dust and noise pollution during extraction and transportation, and proper disposal of waste materials to reduce the environmental impact.