Kimball was dealing with low demand for new subsidiary silver and, like other directors, wanted the Mint to stay out of creation or support for coin speculation. This included issuing proofs to demand not a fixed quantity, and in the 1880s minting unnecessary circulation coins in quantities that, at the time, seemed great enough to prevent price manipulation. He was also concerned about proof sets and in 1889 refused to approve them until Congress had adjourned without acting on discontinuance of the 1, 3 dollar gold, and 3-cent CuNi.