GRAND RAPIDS, Mich. — A Michigan charity that collects donated clothing, shoes and other items for low-income residents got a really old cast-off in a donation box: A mastodon tooth.

The Grand Rapids Press reports the remains of the extinct relative of the elephant turned up during a July pickup in Grand Rapids. The charity called In The Image turned them over to the Grand Rapids Public Museum, which is adding them to its collection.

The tooth is broken into two parts and is covered in lacquer. A tusk, also covered in lacquer, is hollow at one end and also may be from a mastodon.

The museum already has a number of mastodon bones and the new additions will be available for loan to educators for use as a learning tool in schools.