Can I use powdered gypsum or calcium carbonate, instead?
A. Several readers have tried making their clay by mixing finely ground gypsum with a bit of water to make a paste, and then using it in place of joint compound in the clay recipe. Tani say it works. However, when I tried it, the gypsum wasn’t ground finely enough and my clay ended up lumpy. I suppose that means that you will need to experiment with locally available products, and see what happens (be sure to tell us how your clay turned out). Or, it might be easier to use a commercial or “instant” paper mache product from the art store, instead. The commercial products don’t work exactly like the paper mache clay, but they may be close enough – many people use products like PaperClay with excellent results. Q. Is the paper mache clay “archival?” A. The paper mache clay has not been tested in a laboratory, so it can’t be called “archival.” The recipe was created to replace traditional paper mache made with strips of old paper and a paste made from flour and water. Since papers are made
