In big automotive factories, the overspray in the painting bays used to build up on surrounding surfaces. The layers of paint were baked as many as 100 times in the ovens where car bodies were cured. Paint build-up had to be removed from time to time.
Workers (and then collectors) salvaged the colorful layered byproduct, calling it Fordite or Detroit Agate.
No more Fordite. Cars are now painted using a process that produces no overspray. Then came Dee Wilder and her polymer clay experiments. Dee has mastered this bit of trickery. There are many more tricks on her dense and rich Flickr site. What will she think of next?