How can I make sheet copper turn matte black?
When I was in middle school we had an art class where we took a sheet of copper (I think) and wiped it with some liquid that made it turn matte black instantly. We then scraped off the black coating with a sharp tool, thereby re-exposing the copper beneath. Does anyone know how to chemically turn sheet copper black?
- Boston, MA USA
Quickest way to blacken copper is using a sulphur solution. You didn't say how big a piece you wish to blacken. If only a small solution is needed, you may be able to make a solution using match heads and hot water to make a weak solution. You will probably have a hard time finding sulphur or polysulphides to make a true solution. It will work better if the copper is clean prior to wiping with solution. If you don't care about surface texture, the best thing is to sand or preferably sand blast prior to blackening. The duller the sanding the flatter the finish. Leave solution on copper for a couple minutes, you may need to repeat. Rinse and dry between applications.
Good Luck.Wayne M
- Mississauga, Ont., Canada
I have a copper table that when we purchased it which had a smeared black finish to it. My cleaning lady to a metal cleaning product to it and it cleaned off the finish and now it's just clear copper. What can I put on the top to re-create the black smeared look? It appears the manufacturer just put some liquid on it and smeared it.Debbie S
home owner - Menlo Park, California, USA
For those who are looking to turn copper black go to an art supply store and ask for Liver Of Sulphur [linked by editor to product info at Mister Art] . It will blacken copper almost instantaneously. Test on a corner or a scrap first to give you an idea as to how fast it will take effect. Also make sure your copper is not coated with a lacquer and make sure to use in a well ventilated area (the fumes are not toxic but, being sulphur, the smell is very unpleasant).Jon Harty
Artist - Coeur d' Alene, Idaho, USA