Japanese coin/token

The image depicts an ancient, oval-shaped Japanese copper coin known as a "Koban," featuring a distinct square hole in the center. The surface of the coin shows signs of aging with a dark patina, and there are inscriptions above and below the hole, possibly representing characters or symbols. The edge of the coin has visible wear and a sequence of numbers written along the side, which may be an identification or cataloging mark. The background is dark, accentuating the coin's historical craftsmanship and contributing to its antique appearance.