Molly Uranium Glass

Take a look at my recent purchase of a Molly uranium glass bowl. I’m delighted with it as it has fairly thick sides and they glow like crazy! It is now home to my collection.

It seems to be a sample of an Imperial Glass “Molly” Pattern Uranium Depression Glass bowl. 

Here’s more information about it:

• Manufacturer and Pattern: This specific pattern, known as “Molly,” was produced by the Imperial Glass Company, a well-known American glass manufacturer.
• Era: It falls under the category of Depression glass, which was widely produced in the United States during the 1920s and 1930s.
• Material: The “uranium green” aspect refers to the inclusion of a small amount of uranium in the glass mixture during its creation. This uranium is responsible for the glass’s distinctive bright green color and, more notably, its characteristic vibrant green fluorescence when exposed to ultraviolet (UV) light, often referred to as a “black light” glow.
• Features: As seen in your image and described in search results, these “Molly” pattern pieces often feature a decagonal (ten-sided) shape with handles and can include etched floral or vine designs.
• Safety: While uranium glass contains uranium, the radioactivity levels are generally considered very low and not harmful in typical use or display of such items.

What is Molly Uranium Glass?

Based on historical records and collector resources, “Molly Uranium Glass” refers to a specific pattern of uranium glass produced by the Imperial Glass Company during the 1920s, as part of the early Depression-era glassware. Uranium glass is a type of vintage glassware that contains small amounts of uranium oxide (typically 0.25% to 2% by weight, though some pieces reach up to 25%) added during manufacturing to create its signature pale yellow-green hue and fluorescent properties. The “Molly” pattern is a lesser-known but collectible line from Imperial, often featuring octagonal plates or similar tableware with a floral cut design. These pieces glow bright green under ultraviolet (UV) light due to the uranium’s fluorescence, and they may register low levels of radiation on a sensitive Geiger counter.

This pattern is distinct from more famous uranium glass subtypes like Vaseline glass (transparent yellow-green, named for its resemblance to petroleum jelly) or custard glass (opaque yellow). “Molly” items are prized by collectors for their Art Deco influences and rarity, as production of uranium glass halted in the U.S. during World War II when uranium supplies were redirected to the Manhattan Project (1942–1958). Post-war, some production resumed using depleted uranium, but Imperial’s Molly line is primarily from the pre-war era.

History and Production

Uranium has been used as a glass colorant since ancient times—traces appear in Roman mosaics from 79 AD—but modern uranium glass emerged in the early 19th century in Bohemia (now part of the Czech Republic and surrounding areas). German chemist Martin Heinrich Klaproth identified uranium as an element in 1789 and experimented with it as a colorant. Bohemian glassmaker Josef Riedel is credited with commercializing it around 1830–1848, naming early variants “Annagelb” (yellow) and “Annagrün” (green) after his wife Anna Maria. By the 1840s, factories in France (e.g., Baccarat and Choisy-le-Roi) and England (e.g., Whitefriars Glass) were producing it, often for decorative tableware, vases, and household items.

The peak popularity was from the 1880s to the 1920s, coinciding with the Victorian and Edwardian eras’ love for ornate glass. In the U.S., Imperial Glass Company (founded in 1901 in Ohio) adopted the technique for mass-produced pressed glass, including the Molly pattern in the 1920s. This era’s pieces were affordable household items, but economic pressures during the Great Depression influenced designs like Molly’s simple yet elegant floral motifs. Production declined sharply in the 1940s due to uranium shortages for wartime efforts, resuming briefly in the 1950s–1970s with depleted uranium for decorative items only. Today, new uranium glass is rare and limited to artisanal pieces from a few U.S. makers like Fenton or Mosser, but Molly Uranium Glass is exclusively vintage.

Characteristics and Identification

• Appearance: In normal light, Molly pieces have a subtle yellow-green tint, similar to Vaseline glass. The octagonal plates (about 8 inches across) feature a cut floral pattern, giving them a delicate, vintage charm. They are transparent or semi-transparent, made from pressed glass.
• Fluorescence: The hallmark is the bright green glow under UV light (blacklight). This is caused by the uranium ions absorbing UV energy and re-emitting it as visible green light—not related to radioactivity, but to the chemical properties of uranyl compounds.
• Radioactivity: Uranium glass emits low-level alpha, beta, and gamma radiation, but it’s minimal. A Geiger counter might detect it up close (e.g., 150 times background levels for some pieces, or about 2.4 µSv/h), but this drops rapidly with distance. For context, you’d get more radiation from eating a banana (due to potassium-40) or using household electronics.
• How to Spot It:
• Shine a UV light in a dark room—if it glows green, it’s likely authentic uranium glass.
• Check for manufacturer marks: Imperial Glass often used an “I” logo inside a diamond.
• Avoid fakes: Some yellow-green glass uses cerium or iron instead of uranium and won’t fluoresce properly. Molly pieces are specifically from Imperial, so verify patterns via collector guides.

Value and Collecting

Molly Uranium Glass is a desirable and niche collectible, appealing to Depression glass and uranium enthusiasts. Prices vary by condition, rarity, and size:

• Common pieces (e.g., single octagonal plates): $20–$50 each, often sold in pairs.
• Sets or rarer items: $100–$300 for a pair of plates or similar tableware.
• High-end antiques: Intricate Molly vases or full sets can reach $500+, especially if signed or in mint condition. Factors boosting value include manufacturer (Imperial is desirable), era (1920s originals), and fluorescence intensity (higher uranium content glows brighter).

You can find Molly pieces on sites like Etsy, eBay, or antique shops specializing in Depression glass. For example, a pair of 8-inch octagonal Molly plates with floral patterns was recently listed for around $50–$100 with free shipping. Start with a UV light and a Geiger counter (affordable online) to verify authenticity. Communities like Reddit’s r/uraniumglass offer tips and share collections. I am delighted with my retail store purchase of an excellent example.

Be sure to check out some other uranium glass manufacturers.