The effect produced on the plate once the grain has been deposited and the plate has been etched. In other words the grain can both designate the general aspect of the plate as well as the holes of varying depth and regularity in the tone or half-tone areas. In this way grain is a synonym of granulated plate surface used in aquatint work and grain photogravure. The purpose of this grain is to retain and differenciate the greasy -crayon strokes, as does grainy paper, so that the impression will bear a grain. The grain is achieved by graining with a graining machine for stones, with a ball grainer, sand blast, or chemical graining on metal plates.
Transfer paper is grained mechanically with an engraved cylinder.
On stone a grain is used when drawing with lithographic crayons. The word grain is also used to designate the more or less regular surface of paper which lightens the pencil strokes. In fact the grain of drawing paper is such that it cannot compare with the dry precision of smooth paper. Smooth paper often being used with ink for technical drawing. Grainy paper is also used for painting with ink and brushes for much the same reason as for pencil drawing.