An idiophone, the lithophone is a set of rocks — granite, fossilized coral, petrified wood, and other melodious stones — that are played by striking them. They’ve been made in a variety of forms all around the globe, some from thousands of years ago. Vietnam’s ancient lithophone is called a dan da, and can be seen in the 2014 demonstration above.
Related reading: Petoskey Stone.
Enjoy more of Kaufmann’s twinkling wrenches and bolts on this site: Beethoven’s Ninth on a Toolbox Glockenspiel.