Two preferred metals for intaglio printing are copper and zinc. These metals are soft enough to be inscribed with a needle, scraped and burnished, but hard enough to allow lines and tones to be bitten by a mordant without causing brittle edges.
Intaglio printmaking includes etching, engraving, drypoint, aquatint, spitbite and mezzotint.
Copper and zinc plates can be polished and unpolished. Gauges are usually 16 to 20 gauge.
Is using copper harmful to my health? Ingesting copper is dangerous. Copper toxicity is the consequence of ingesting large amounts of the metal. (National Institute of Health: www.nlm.nih.gov/medlineplus/ency/article/002496.htm)
We use copper in printmaking in ways that do not involve absorbing significant amounts through the mouth, nose, skin, or respiration.
Is using zinc harmful to my health? Like copper, zinc ingested in significant amounts can cause zinc toxicity. (National Institute of Health: ods.od.nih.gov/factsheets/Zinc-HealthProfessional)
Most of the health problems associated with copper or zinc occur from the materials used to process and work on the copper plate. These include acids for etching, tools used to cut, inscribe, stipple and file the copper plate, materials used for ground, inks and cleaners. (Artist Beware, Michael McCann, The Lyons Press, 2005, pg. 323.)
- Copper, Cu on the Periodic Table of Elements is named for cyprium, or Cyprus where copper was mined in the Roman Era.
- Zinc, Zn, was allegedly named by Paracelsus, after the German zinke, “jagged,” to describe the way it behaved in a furnace.
- Copper has been mined and used by humans for the past ten thousand years.
- According to projections, there will be no new copper to be mined in 25 to 60 years.
- Eighty one percent of all the copper mined over the past millennium is available.
- Most copper used is recycled with unknown “provenance.”
- 70% of zinc used is mined; 30% is from recycled metal.
- Brass is copper combined with zinc. Brass has been used since at least the 10th c BC.
- Bronze is copper combined with tin. Brass has been in use since around 4000 BC.
- Used in industries (building) and arts for millennium, current uses of copper also include semi-conductors and circuit boards.
- Zinc, the 24th most abundant element in the world, is used in a variety of alloys and compounds which have a range of uses, including use in batteries, sunscreen, deodorants, shampoos, and paints.
- Goldsmiths engraved copper, rubbed an alloy into lines and printed their designs as a record. Engraving in Germany and later in Italy and the Netherlands flourished in 1445—1550 when etching became the more popular printing technique.
- Engraving on copper is still used for banknotes and passports.
- Lines in copper are bitten more evenly than in zinc and color is less distorted from copper than zinc.
- The Statue of Liberty is the largest copper sculpture in the world.
- Copper is a dietary mineral, essential for the respiratory enzyme complex.
- Copper and zinc compounds in high amounts can be poisonous to humans.
- Good food sources of copper are mollusks and crustacea with amounts in many meats.
- Living organisms rely on zinc as a valuable nutritional trace element. Food sources include seeds and whole grains.
- As a dietary supplement, zinc is thought to have antioxidant properties and supports the immune system. It is used to treat diarrhea in children, helps speed healing processes after injuries and might decrease the duration and severity of cold symptoms.