A set of six, 22 cm diameter, transparent, shallow glass plates. These plates are made of a uranium-loaded, yellowish glass and were made starting as early as 1830 and continued to be made until the early 1940s when uranium ore became much more valuable because it became a source of fuel for the nuclear industry. There are no marks to indicate a manufacturer of the artifacts. The glass is also sometimes called Depression Glass and the loading of uranium dioxide varied from about 0.1% to 25 % depending on the factory. The plates emit a green glow when under ultraviolet lighting.
