Abstract: An alloy including at least 6 weight percent aluminum, greater than 6 weight percent nickel, and at least 50 weight percent copper. In some embodiments, the alloy includes 6 to 9 weight percent aluminum, 6 to 11 weight percent nickel, 1.5 to 3 weight percent iron, 1.5 to 3 weight percent manganese, 1 to 3 weight percent silicon, 1 to 5 weight percent tin, and 75 to 80 weight percent copper. The alloy is particularly suitable for jewelry, e.g., wrist watches, and materials exposed to aquatic environments for extended periods of time, e.g., boat hulls and boat propellers.