One of the more common etching techniques is “Dry Point,” which consists of making incisions directly onto the metal plate; etching with a “Buril”, differs from dry point etching because of the tool used which is similar, only that in this case the points used are triangular which differ from the first which is round. Another direct technique on metal is “Mezzotinta” or manera Negra , which consists of the use of a special tool for this technique called Cuna or Berseau, which allows creating a fine texture over the whole plate in order to later burnish the parts which one may wish to flatten or smooth to create the contrast between light and shadow.
In etching al “Aguafuerte”, the plate may be covered with different varnishes depending on the sought-after result, in order to later draw upon the varnish lifting this with a point but without etching the metal. Later, this plate is submerged in an acid bath, (etching solution), which penetrates in the drawn lines etching them, (hollow etching), and the longer it is left in the acid, the deeper the line will be made.
Different techniques can be combined for metal etching, such as dry point and aguafuerte, aguafuerte and aguatinta, aguatinta and sugar, etc. The more frequent metals for this technique are copper, zinc, tin, steel, etc.