A very popular type of collectible, old green glassware is often known as Vaseline glass. Generally speaking, the glassware in this category is colored green by adding uranium to the glass while it is being made. Interestingly, to instantly determine if green glassware has uranium in it, you can turn out the lights, turn on a UV light or black light, and the glass will turn a fluorescent green. Using a black light isn’t necessarily a definitive test for whether the glassware has uranium in it or not, since some types of green glassware that contain uranium won’t fluoresce under the light.
History of Green Glass
The uranium that gives the green glassware its unique color was first used in the 1830s, and was used from that point on to manufacture the glass. Production of the unique green glassware stopped for about 15 years starting at the beginning of World War II. By 1959, manufacturers were making green glassware again, but now the glass was being made with depleted uranium instead of natural uranium. Even today, some companies still make this kind of glassware and still add uranium to it, but the only items being made today are for decorative purposes. Companies do not make dinnerware out of the green glassware since we now know more about some of the effects of uranium on humans.
Even though there was some concern about the uranium and radiation exposure, it was proven that the levels just aren’t that high and probably won’t cause any damage. Drinking glasses were made for a while after World War II, but it was proven that when water is added to the glass and allowed to sit for a specific period of time, the uranium does leach out into the water. However, the next time the glass was filled up, the amount of uranium that eventually transferred to the water was less. The conclusion was reached that the amount of available uranium that could be leached out into the liquid became less and less after each refill.
Green glassware or Vaseline glass is a unique collectible with a very interesting history. Even though uranium is and was used to make the green glassware, generally the amount of uranium the glass emits is low enough to be a non-factor. Green glassware has a unique and rather odd color, but it can be quite attractive and some collectors prefer its uniqueness to any other type of collectible glass.