fordite

thumb|291x291px|Fordite in Dearborn, Michigan, 2019 Fordite, also known as Detroit agate, Motor City agate, paint rock, or paint slag, is a lapidarist term for polished pieces of finely layered paint masses from automobile factories. The masses consist of automotive paint which has hardened sufficiently to be cut and polished. It was formed from the progressive buildup of layers of enamel paint on tracks and skids on which cars were painted with acrylic lacquer, which have been baked numerous times. In recent times the material has been upcycled into jewelry.

Fordite is notable for the way it displays "the history of the American automotive industry", both to illustrate the changing colors of car paint as well as the transformation and disappearance of the Ford Motor Company factories in Detroit.