21 × 29 cm
Etching is traditionally the process of using strong acid to cut into the unprotected parts of a metal surface to create a design in intaglio (incised) in the metal. As a method of printmaking, it is, along with engraving, the most important technique for old master prints, and remains in wide use today.
In traditional pure etching, a metal (usually copper, zinc or steel) plate is covered with a waxy ground which is resistant to acid. The artist then scratches off the ground with a pointed etching needle where he or she wants a line to appear in the finished piece, so exposing the bare metal.