The coin is 30mm (about 1 1/8") in diameter. The front bears the familiar logo of Lewis and Clark with the reverse featuring the expedition's keel boat and a group of lodges in recognition of the contribution of the various Indian tribes toward the success of the expedition. Die struck in bronze, copper and .999 fine silver, each coin is furnished in a lucite capsule in a plastic flip that includes an information card. State correct metal when ordering.