Is Uranium Glass Jewelry Safe to Wear?
This question was certainly on my mind as I gathered these fascinating glowing stones in preparation for my upcoming collection.
As someone who dons a large uranium glass ring on my finger nearly every day, I had already accepted the internet’s assertion that it was perfectly fine to wear this material. However, the truth can be nebulous in virtual spaces, and I needed a much more official answer before releasing a hundred pieces of uranium glass jewelry out into the world.
First a little history: Who put uranium in glass and why?
The practice of adding small amounts of uranium to enhance the color of glass and pottery glaze traces back nearly 2000 years. Archeologists in Italy discovered an ancient Roman mosaic wall from the year 79 AD with greenish-yellow tiles containing the element.
The Czech Republic is the true “birthplace” of uranium glass as we now know it. There are accounts of “pitchblende,” a mineral containing uranium ore, being used in glassblowing in this region as early as the Middle Ages. However, it wasn’t until the 1830s that Franz and Josef Reidel began to regularly implement uranium oxide into their company’s commercial glasswork.
Also known as “canary glass” (and later classified as either “vaseline” or “depression” glass), this vibrant yellow-green material truly took off in the 1880s. Its international popularity lasted through most of the 20th century, as it ubiquitously appeared in kitchen & dining ware, vases, lamps, figurines, marbles, and more. Unfortunately, during WWII, the US had to halt production for nearly 2 decades as the government confiscated all uranium for use in the Manhattan Project.
Albeit less popular now than in its heyday, new uranium glass pieces are still being produced today by companies such as Fenton and Mosser, and in recent years there has been a resurgence of popularity among vintage and oddity enthusiasts. While green is the most common color, you will find shades of yellow, white and blue as well. You can tell that glass contains uranium oxide if it fluoresces bright green under a blacklight.
So, is it safe? Short answer: yes.
I contacted several experts in the field including a physicist, geologist, & radiation safety officer, and they were all of the general opinion that uranium glass jewelry is totally safe to wear. However, being scientists, they recommended I get a definitive answer by testing my stones with a geiger counter.
I do have my own geiger counter, but it’s from the 1950s and I don’t think it’s been turned on since that decade. Check out the battery on this thing!
The ones they sell on Amazon are also not very reliable according to the experts, and I didn’t have the money to shell out for a highly sensitive scientific meter. Thankfully, Allison, the radiation safety officer I’d been speaking with, invited me to visit the lab at Boston University to test the stones with her equipment. She also gave me an in-depth lesson on radiation, and this is what I learned:
There are different forms of radiation waves that we encounter in the world. We discussed alphas, betas, gammas, and x-rays. Alpha waves are slow and heavy, and can’t pass through something as thin as a piece of paper. Beta waves are a little faster, but can be blocked by plastic or a thin sheet of metal (such as the silver in my jewelry). Gamma and x-rays are faster and can easily pass through people and most thin materials, as we know from airport and hospital visits. They require something heavier like lead to obstruct their path.
We are exposed to a very low dosage of these waves every day from various natural and manmade sources. Cosmic radiation from the sun and stars is a constant, and radioactive elements such as uranium, thorium and potassium are also present in many everyday items such as granite, bricks, concrete, electronics, smoke detectors, soil, bananas, lettuce, asparagus and tap water, to name a few.
So, flying in a plane, living at a high altitude, having granite countertops, being near mountains, and eating salad are all potential sources of radiation exposure. However, this exposure is relatively light and part of normal life, not posing any great risk to our health.
Uranium glass is primarily an alpha wave emitter. The slow alpha waves will mostly stay contained within the glass itself, and the ones that escape can be stopped in their path by a thin material like fabric, paper, or even skin.
Alpha waves are only potentially dangerous to our body if they are consumed or inhaled, so it is not recommended to breathe in or swallow uranium glass dust.
There are different schools of thought on whether one should use uranium glassware for eating and drinking, but the general consensus is just to avoid chipped items or exposing them to highly acidic liquids like juice or wine, as this could possibly leach heavy metals out of the glass.
At the Boston University Environmental Health & Safety Department lab, we used a Ludlum 320 geiger counter with a Model 44-9 GM pancake probe that detects alpha, beta and gamma radiation. We tested each of my uranium glass cabochons individually to see what dosage they emit.
Most of the stones gave negligible counts, not reading above normal background radiation levels. There were a few pieces that registered slightly higher, so we conducted an experiment by placing a piece of paper over them and taking the reading again. With paper blocking the stone, they dropped back down to background levels, telling us that, as expected, the waves were primarily alpha. Therefore, not concerning.
Allison also tested some of my finished jewelry pieces in which the stones are bezel-set in sterling silver, and she found there was no significant reading on the silver-facing side of each piece. The metal fully blocked all alpha and beta waves, and no notable gammas were detected.
One additional observation was that the content of uranium oxide used in this glass usually accounts for less than 2% of the object’s total make-up. When you take into consideration how small most of these stones are, it further assuages any exposure worries.
She concluded that it is indeed safe to handle and wear the uranium glass stones used in my jewelry.
As I left the lab, Allison offered me one last statistic: the Nuclear Regulatory Commission conducted an extensive study in 2001 and found that the yearly radiation exposure uranium glass collectors receive from their pieces is only about 1% of the total radiation they are exposed to yearly through natural and environmental factors.
It was relieving to finally get a professional opinion on the matter of uranium glass safety. This whole experience has put my mind at ease and I hope it’s done the same for you.
Happy collecting and wearing!
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