The solution chemistry of carbonate and implications for pyrite flotation in the presence of lizardite have been investigated. The results show that lizardite causes problems in the flotation of pyrite, by adhering to the pyrite particles. Addition of various reagents which can produce carbonate has been found to improve pyrite recovery during flotation. The solution chemistry of carbonate indicated that carbonate mainly exists in the form of CO32- ions in the pH range that carbonate can restore pyrite flotation recovery. When the reagent producing the carbonate ion is able to provide it at a higher concentration, the pyrite flotation performance is improved. (C) 2013 Elsevier Ltd. All rights reserved.