In 1883, the Philadelphia Mint struck copper patterns for a Hawaiian coinage. Charles Barber designed the coins and, from his dies, Mint employees produced eighteen sets of proof copper versions of the 1/8th Dollar (Hapawalu), the Quarter Dollar, the Half Dollar, and the Dollar. The Dime was excluded because it had not yet been considered as a denomination, but was included, later, in the regular silver Proof sets.
Today, all of these copper Patterns are extremely rare amd highly prized.