American Clay.  Lime Putty can be used as an additive to the maker’s Earth Plasters or mixed to make limewash. When added to plaster, the putty “gauges” or hardens the plaster, resulting in a harder finish — maximum hardness is achieved over about six months. Lime Putty can be added to all American Clay applications, including the two-coat process original plasters and commercial single-coat Enjarre plaster. Adding the putty to the second plaster coat increases square-footage coverage by about 10%. Plaster application procedures remain the same. 866.404.1634.