In intaglio printmaking, what material is commonly used for the printing plate?

In intaglio printmaking, copper or zinc is the most commonly used material for the printing plate due to several key characteristics that make these metals suitable for this technique. Intaglio involves incising a design into a surface, and the plates are then inked, with the ink only filling the incised lines. Copper and zinc plates can be etched, engraved, or drypointed to create fine details, allowing artists to produce intricate images with high levels of tonal variation.

Copper, in particular, is favored for its softness, making it easier to work with and allowing for fine detail in the incised lines. Zinc, while harder than copper, offers a more economical alternative and is also commonly used in professional printmaking settings.

Other materials listed, such as wood, plastic, and glass, don't suit the specific requirements of intaglio printmaking. Wood is typically associated with relief printing processes, where the raised surface is inked, while plastic may not hold fine details as effectively as metal. Glass, on the other hand, is primarily used in techniques like lithography or for other purposes, but does not serve well as an intaglio plate material due to its fragility and lack of the necessary ink-holding capacity.