Public and artistic opinion of the new pieces was, and remains, mixed. In 1915, Mint officials began plans to replace them once the design's minimum term expired in 1916. The Mint issued Barber dimes and quarters in 1916 to meet commercial demand, but before the end of the year, the Mercury dime, Standing Liberty quarter, and Walking Liberty half dollar had begun production. Most dates in the Barber coin series are not difficult to obtain, but the 1894 dime struck at the San Francisco Mint (1894-S), with a mintage of 24, is a great rarity.