This is Bob Myers from the Historical Society of Michigan with a Michigan history moment. It's a valuable jewelry and it's called Fordite or motor agate. But what is Fordite? In short, Fordite is a sort of synthetic gemstone that looks much like an agate. It's made up of layers and layers of automobile paint, hence Fordite. The earliest automobiles were brush painted in the fashion of horse drawn carriages. It took a long time to paint a car, and the paint job did not hold up well. As the demand for automobiles grew in the early 20th century, manufacturers looked for ways to speed up the process. The Ford Model T dominated the market for years, rolling off the assembly line by the millions. The first Model Ts from 1908 through 1912 came in red, gray, green, or blue, but were not available in black. From 1915 until 1926, the Model T came only in black. Although Ford used more than 30 different types of black paint, competing auto companies offered multiple colors, which eventually forced Ford to abandon its black paint only policy. In 1924, spray guns were introduced to the auto assembly line. Spray guns allowed workers to paint the cars more quickly and gave a more consistent finish than brush painting. Spray painting cut the finish time by 2/3. The there was just one problem, overspray. Most of the paint went on the car body, but some collected on the tracks and skids that carried the cars. After painting, the assembly line carried the car into an oven that baked on the finish. Naturally, the paint baked onto the tracks and skids as well. That eventually built up in thick multicolor coats of baked paint that the workers had to break off. The result? Chunks of Fordite, also known as motor agate. Today, motor agate is made into all sorts of beautiful jewelry. Cut to shape and polished. Fordite is a highly desirable material. Unfortunately for Rockhounds, automobile assembly lines no longer produce it. New painting technology has virtually eliminated overspray, so paint doesn't build up on the assembly line. Today's supply of Fordite comes from autoworkers who brought home chunks of the material years ago. This Michigan history moment has been brought to you by michiganhistorymagazine.org.