Uranium glass was first discovered in 1789 and was soon made into decorative glass because of its fluorescent effect. It used to be made into tableware and household items but was no longer widely used during the Cold War.
Uranium glass can be yellow, green, or blue, depending on the oxidation state and concentration of metal ions. Under ultraviolet light, it fluoresces bright green.
The most common color of uranium glass is pale yellowish green and was named after petroleum jelly. The term Vaseline glass is sometimes used to refer to all translucent glass.
There are several common subtypes of uranium glass, including:
1. Custard glass
2. Jadeite glass
3. Intaglio glass
4. Burmese glass
The usage of uranium glass dates back to the late Middle Ages, when pitchblende was extracted from the Habsburg silver mines in Jáchymov, Bohemia, and used as a dye.
Uranium glass is used in glass-to-metal seals and serves as an intermediate glass.
Franz Xaver Riedel was a prolific manufacturer of uranium glass in Niederpolaun, Bohemia.
In the 1840s, many European glassworks began producing uranium glass. Baccarat, for example, created a green uranium glass called chrysoprase.
How is uranium glass made?
Glassmakers discovered that uranium glass could be tempered with certain mineral additives at high temperatures, creating increasingly opaque glass. This material, which is technically glass ceramic, was given the name “Vaseline glass” because it supposedly resembles Vaseline.
This video shows you how to spot uranium glass, performs a quick experiment, and gives you a quick overview of the market and its price:
Glass containing uranium is banned for commercial use. Nevertheless, glassmakers devised other methods to achieve the green color without the use of uranium. Uranium is still visible in the glass if you use a UV flashlight.