Exposure to the hands from the beta particles emitted by radionuclides in the glass NUREG-1717 estimated the following exposure rates from two different pieces of glass with 10% by weight uranium content:ġ footę x 10-4 mrem/hr 1.8 x 10-3 mrem/hrĦ feetĒ.5 x 10-5 mrem/hrĕ x 10-5 mrem/hrįor comparison, the background exposure rate due to gamma rays is approximately 1 x 10-2 mrem/hr.Ģ. The principle gamma rays emitted by these nuclides would be 63 keV and 93 keV from Th-234 and 186 keV from U-235. Exposure to the body from the gamma rays emitted by radionuclides in the glass.Ĭhemically processed uranium of the sort we are considering here consists of the following radionuclides: U-238, Th-234, Pa-234m, U-234, U-235 and Th-231. There are three principal radiation exposure pathways associated with Vaseline glass:ġ. Nevertheless, the uranium content of some glass manufactured in the early 1900s, reached as high as 25%.Ī very detailed analysis of the radiation exposures due to uranium in glassware can be found in the Nuclear Regulatory Commission publication “Systematic Radiological Assessment of Exemptions for Source and Byproduct Materials” (NUREG 1717). The uranium content of Vaseline glass is often on the order of 2% by weight. No dinnerware is being made.īuckley et al (1980) estimated that there were at least 4,160,000 pieces of decorative uranium glass produced in the US between 19 and 15,000 drinking glasses from 1968 to 1972. are still making Vaseline glass (e.g., Boyd Crystal Art Glass, Mosser, Summit Glass and Fenton Glass), but it is exclusively of the decorative variety. At present (2004), a few companies in the U.S. Prior to World War II, natural uranium was used, but when Vaseline glass production resumed in 1959, the switch was made to depleted uranium (DU). Uranium was first used to color glass in the 1830s and it has continued to be used for this purpose with the exception of a fifteen year (or so) period beginning in World War II. Some uranium-containing glass does not fluoresce under ultraviolet light, e.g., the yellow glass "gemstone" does not fluoresce under UV despite the fact that it contains uranium! This green fluorescence explains why an example of Vaseline glass that looks yellow under incandescent lighting might take on a greenish tinge when viewed outdoors. If the glass glows a rich green color, it contains uranium. Perhaps the most reliable way to identify the presence of uranium in the glass is to expose it in the dark to a source of ultraviolet light (e.g., a black light). To confuse matters somewhat, this non-Vaseline glass might even be radioactive due to the presence of thorium impurities! Some transparent yellow or yellow-green glass has been colored using additives other than uranium (e.g., cerium oxide), and it can look exactly like Vaseline glass. Canary glass is an even older name that was first used in the 1840s to describe what is now referred to as Vaseline glass. Uranium glass, an older and more general term, is sometimes used as a synonym for Vaseline glass, but this can lead to confusion because some types of glass colored with uranium (e.g., custard glass and Burmese glass) are opaque whereas Vaseline glass is transparent. Vaseline glass is a recent term that probably dates from the 1950s. They might describe it as “Depression Glass,” a less desirable commodity. Purists might argue that a green sugar bowl should not be considered Vaseline glass because an additional colorant (probably iron) has been used in addition to the uranium to produce the green. Vaseline glass, like the candlestick holder shown here, is a term for the transparent yellow to yellow-green glass that owes its color to its uranium content.
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