To prevent the sides from caving in as the mine goes deeper and deeper, the cut is made to form terraces, or steps. Individual working levels on the excavating side of the mine are called benches.
Për të parandaluar shembjen e faqeve anësore me dhé, ndërkohë që miniera bëhet gjithnjë e më e thellë, gërmohet duke formuar tarraca ose shkallë.