Another short video clip of a large agatized, fossil coral “geode” from Florida filled with druzy quartz. This fossil coral is Miocene (25-32 million years) in age, and was formed when fine sediments covered shallow coral reefs. As silica rich groundwater through the rock that was formed (and exposed as sea-levels dropped), it replaced the calcium carbonate skeleton of the coral with Chalcedony.
Fordite, also known as Detroit agate, is old automobile paint which has hardened sufficiently to be cut and polished. It was formed from the built up [sic] of layers of enamel paint slag on tracks and skids on which cars were hand spray-painted (a now automated process), which have been baked numerous times.