Uranium glass glows bright green under a blacklight — that eerie glow is the same property that makes uranium glass one of the most distinctive and widely collected categories of antique glassware. Made from the 1830s through the 1940s (and briefly revived afterward), uranium glass was produced by adding uranium oxide to the glass batch, creating colors ranging from pale yellow to deep green. Today it attracts collectors for its beauty, its history, and yes, that unmistakable UV glow.
What Is Uranium Glass?
Uranium glass (also called vaseline glass, Depression glass, Custard glass, or Burmese glass depending on color and era) is glass that contains uranium oxide as a colorant. The uranium content typically ranges from 0.1% to 25% by weight, with most pieces containing 1–2%.
The uranium creates a characteristic fluorescence: under ultraviolet (blacklight) illumination, uranium glass glows a bright, unmistakable green. This UV fluorescence is the most reliable single test for identifying uranium glass — no other glass produces quite the same intense green glow.
A Brief History of Uranium Glass
Uranium glass production spans nearly two centuries:
| Era | Period | Notes |
|---|---|---|
| Early production | 1830s–1880s | Bohemian glassmakers pioneered uranium coloring; elegant art glass pieces |
| Victorian / Edwardian | 1880s–1914 | American and British factories produced pressed and blown pieces |
| Depression-era peak | 1920s–1942 | Mass-produced tableware (plates, cups, bowls, pitchers) in yellow-green and pale green |
| WWII halt | 1942–1958 | U.S. government classified uranium as a strategic material; commercial production stopped |
| Post-war revival | 1958–present | Production resumed at reduced scale; limited modern collectibles (Fenton, Mosser, others) |
Is Uranium Glass Dangerous?
This is the question every uranium glass collector is asked first, and the short answer is: uranium glass is safe for handling and display under normal conditions. Here’s the detailed breakdown:
Radiation Level
Uranium glass is mildly radioactive — but so is granite countertops, Brazil nuts, and bananas. The radiation from a typical piece of uranium glass is in the range of 1–5 millirem per year at contact distance, compared to a U.S. average background radiation exposure of about 310 millirem per year from natural sources. The U.S. Nuclear Regulatory Commission (NRC) and health physicists consistently classify uranium glass as presenting no significant radiation risk.
A Geiger counter placed directly against uranium glass will click faster than background — this alarms some people, but faster-than-background is not the same as dangerous. The radiation type is primarily alpha particles (blocked by a sheet of paper or your skin) and low-level gamma rays at levels well below any health threshold.
Safe Practices
- Handling: Safe to handle with bare hands. Wash hands after prolonged handling — the same practice as with any antique.
- Display: Safe for open display in the home. A cabinet collection of uranium glass does not meaningfully increase household radiation levels.
- Food and drink use: This is where opinions differ. The NRC says the glass itself is safe for food use since uranium is locked in the glass matrix and doesn’t leach under normal conditions. However, most collectors and antique dealers recommend against using uranium glass for everyday food and drink — particularly acidic foods like citrus, vinegar, or tomato sauce — as a conservative precaution. Decorative display only is the standard collector practice.
- Pregnant women and children: No specific prohibition from health authorities, but many collectors keep uranium glass as display items only, which is a sensible approach for any antique glass.
- Breaking glass: Broken uranium glass creates glass dust. Clean up broken pieces with care — same precautions as broken glass generally, plus avoid inhaling dust. This is not a uranium-specific concern; any fine glass dust is a lung irritant.
Bottom line: Uranium glass is one of the most studied “radioactive everyday objects” precisely because collectors and regulators take it seriously. The research consistently concludes it is safe for collection and display.
How to Identify Uranium Glass
The Blacklight Test (Most Reliable)
The UV blacklight test is definitive. In a darkened room, hold a UV blacklight (365nm wavelength works best; 395nm also works) near the glass. Uranium glass will glow a bright, saturated green — not just a faint shimmer, but a strong, distinctive fluorescence. No other glass produces this specific color and intensity under UV.
Inexpensive UV flashlights (385–395nm) are widely available and work well for field identification. A 365nm blacklight produces a more accurate fluorescence test and is preferred by serious collectors.
How to Tell Uranium Glass Without a Blacklight
Without a blacklight, uranium glass can be identified by color and context:
- Yellow-green “vaseline” color: The most common uranium glass color is a translucent yellow-green that resembles petroleum jelly (vaseline). Hold it to natural light — it glows slightly even in daylight due to UV content in sunlight.
- Custard color: Opaque creamy yellow glass, used in Victorian and early 20th-century art glass pieces.
- Depression-era green: The pale, transparent green of many Depression glass pieces (Anchor Hocking’s “Forest Green” and Hocking’s “Emerald Green” from the 1950s are uranium glass).
- Context: Pressed glass patterns from the 1900–1940 period in yellow-green are strong candidates. Art glass pieces (Burmese, Peachblow, Amberina) from 1880–1910 era are very frequently uranium glass.
- Sunlight test: Genuine uranium glass often appears to glow slightly in strong sunlight (the UV component of sunlight triggers weak fluorescence visible to a trained eye).
Colors That Are Uranium Glass
| Color Name | Description | Common Era | Glows Under UV? |
|---|---|---|---|
| Vaseline | Translucent yellow-green, petroleum jelly appearance | 1880s–1940s | Yes — bright green |
| Custard | Opaque creamy yellow | 1880s–1920s | Yes — bright green |
| Canary yellow | Transparent deep yellow | 1880s–1940s | Yes — bright green |
| Pale / Depression green | Transparent light green | 1920s–1940s | Yes — bright green |
| Chartreuse | Yellow-green, slightly more green than vaseline | 1940s–1960s | Yes — bright green |
| Burmese | Pink to yellow gradient, heat-sensitive | 1885–1895, revival 1970s | Yes — green from yellow portion |
| Topaz | Clear yellow-amber | 1920s–1930s | Yes — bright green |
| Aqua / Teal uranium | Blue-green shades (less common) | 1880s–1920s | Yes — green |
Glass That Looks Like Uranium Glass But Isn’t
- Sea glass (beach glass): Green sea glass does not glow under UV. The green color comes from iron, not uranium.
- Modern reproductions in uranium colors: Some modern glass is made in vaseline-yellow colors without uranium. The UV test is definitive — non-uranium glass will not produce the same bright green fluorescence.
- Manganese glass: Some glass containing manganese oxide fluoresces pale blue or blue-white under UV — completely different from uranium’s green.
- Depression glass in green or amber: Not all Depression glass is uranium glass. Many Depression glass pieces (particularly clear, pink, and blue) contain no uranium. The UV test is required to confirm.
Vaseline Glass vs. Uranium Glass
The terms “vaseline glass” and “uranium glass” are often used interchangeably, but there are distinctions:
- Uranium glass is the broad category — any glass containing uranium oxide, regardless of color. This includes custard glass, Depression glass green, Burmese glass, and vaseline glass.
- Vaseline glass is a subset of uranium glass — specifically the translucent yellow-green glass that resembles petroleum jelly (vaseline). The American term “vaseline glass” is used primarily in the U.S.; British collectors generally call the same glass “uranium glass.”
In practice: all vaseline glass is uranium glass, but not all uranium glass is vaseline glass. When dealers say “vaseline glass” they specifically mean the petroleum jelly-colored pieces. When they say “uranium glass” they may mean any piece that glows under UV, in any color.
The Uranium Glass Collectors Association (UGCA) uses the term “uranium glass” to cover all UV-fluorescent glass containing uranium, while recommending “vaseline glass” specifically for the translucent yellow-green variety.
Uranium Glass Value Guide
Uranium glass values vary enormously based on pattern, era, maker, form, color, and condition. Here are broad ranges:
Common Depression-Era Uranium Glass (1920s–1942)
| Piece Type | Value Range | Notes |
|---|---|---|
| Small plate (6–8 inch) | $5–$25 | Common patterns; vaseline/pale green |
| Dinner plate (10 inch) | $15–$45 | Pattern and condition dependent |
| Cup and saucer set | $10–$35 | Uranium Depression glass sets |
| Tumbler / glass | $8–$30 | Paneled or plain; vaseline |
| Sugar and creamer set | $20–$60 | Common vaseline patterns |
| Butter dish (with lid) | $35–$120 | Pattern and condition critical |
| Pitcher | $40–$150 | More valuable with uranium glow vs. plain green |
| Serving bowl | $20–$75 | Vaseline and Depression green |
| Cake stand | $45–$150 | Pedestal forms command premium |
| Candlestick pair | $25–$80 | Period uranium candlesticks |
Victorian and Edwardian Art Glass (1880s–1915)
| Piece Type | Value Range | Notes |
|---|---|---|
| Vaseline glass cruet | $75–$300 | Pattern, stopper, condition |
| Vaseline glass toothpick holder | $30–$100 | Common form in high demand |
| Vaseline glass vase (pressed) | $40–$175 | Pattern and size dependent |
| Custard glass piece (Northwood, Heisey) | $25–$200+ | Marked pieces at premium; rare patterns $500+ |
| Burmese glass vase (Mt. Washington) | $200–$2,500+ | Acid finish vs. shiny; decorated vs. plain |
| Burmese glass piece (Webb England) | $150–$1,500+ | Quality comparable to Mt. Washington |
| Uranium opalescent glass | $50–$400 | Northwood, Fenton opalescent in uranium |
| Art glass pitcher (uranium base) | $100–$600 | Maker and pattern critical |
Factors That Increase Uranium Glass Value
- Strong UV fluorescence: Pieces with bright, intense glow command a premium over weak-glowing pieces
- Rare colors: Deep canary yellow, aqua uranium, and certain Burmese color transitions
- Known maker marks: Northwood, Heisey, Fenton, Cambridge, Mt. Washington Burmese
- Unusual forms: Cruets, toothpick holders, unusual vase shapes, covered pieces
- Enameled decoration: Painted flowers, gold trim, applied decoration
- Complete sets: A full uranium glass water set (pitcher + 6 tumblers) worth more than sum of parts
- Victorian era: Pre-1920 pieces generally command higher prices than Depression-era
Where to Find Uranium Glass for Sale
- eBay: The largest single marketplace; search “vaseline glass,” “uranium glass,” or “uranium Depression glass”
- Replacements Ltd.: Carries both patterns and individual pieces
- Etsy: Smaller dealers, often good for single decorative pieces
- Ruby Lane: Higher-end dealers with quality Victorian examples
- UGCA Shows: The Uranium Glass Collectors Association hosts specialist shows with dealers who know their stock
- Antique malls: Common finds in the Midwest and Southeast; bring a small UV flashlight
- Estate sales: One of the best sources — uranium glass is often undervalued by non-specialist sellers
How to Collect Uranium Glass
Starting a Collection
New collectors often start with Depression-era uranium glass because it is affordable ($5–$50 per piece) and widely available. Vaseline glass in classic pressed patterns (Hobnail, Opalescent Hobnail, Cable, Daisy and Button) makes a good entry point. From there, collectors typically specialize into a particular era, maker, or form.
Bring a UV flashlight to every antique shop, estate sale, and flea market. Many dealers and sellers do not know they have uranium glass — finding it at non-collector prices is entirely possible.
Authentication at Antique Sales
A 365nm or 385nm UV flashlight that fits in a pocket is the essential tool. At a sale, cup your hand around the piece and light it briefly to see the fluorescence. The green glow is unmistakable. Modern reproductions in uranium colors but without uranium do not glow. A piece labeled “vaseline glass” that doesn’t glow is misidentified — don’t buy it at uranium glass prices.
Care and Display
- Cleaning: Warm water with mild dish soap, hand washed. Avoid dishwashers — the high heat and harsh detergents can damage the surface finish and etch the glass.
- Display: A blacklight display — a strip of UV LEDs behind or under your collection — dramatically showcases the glow. Many collectors display uranium glass with built-in UV lighting in their cabinets.
- Storage: Individual padding between pieces; avoid stacking without protection. The glass is no more fragile than other antique glass, but chips reduce value significantly.
- Condition: Chips and cracks reduce value 50–80%. Cloudiness (glass sickness from washing or humidity) reduces value significantly. Scratches on pattern surfaces reduce value 20–40%.
Frequently Asked Questions About Uranium Glass
Is uranium glass safe to own?
Yes. The U.S. Nuclear Regulatory Commission classifies uranium glass as a exempt quantity radioactive material that poses no significant health risk for collection and display. The radiation level from a typical piece is well below background radiation levels at any distance beyond a few inches.
Does uranium glass glow in the dark?
No. Uranium glass does not glow in the dark on its own — it requires an ultraviolet light source to fluoresce. In normal light, uranium glass appears as colored glass (yellow, green, or amber). Only under UV does the bright green glow appear.
What is vaseline glass vs uranium glass?
Vaseline glass is a specific type of uranium glass — the translucent yellow-green variety that resembles petroleum jelly. All vaseline glass is uranium glass, but uranium glass includes other colors (custard, Depression green, Burmese, canary yellow). The UV test is the reliable confirmation for both.
How do I identify uranium glass without a blacklight?
Look for the characteristic vaseline yellow-green color in pressed glass from the 1880s–1942 period. Hold it to daylight — genuine uranium glass may show a faint glow in strong sunlight due to UV content. Custard glass (creamy opaque yellow), canary yellow pieces, and Depression-era green glass are all good candidates to test. The blacklight test is the only definitive confirmation.
Is uranium glass valuable?
Values range from $5 for common Depression-era pieces to $2,500+ for Victorian art glass like Mt. Washington Burmese or decorated Northwood custard glass. Most common Depression-era uranium glass sells for $10–$75 per piece. Victorian vaseline glass in unusual forms (cruets, toothpick holders, vases) typically ranges from $50–$300. Rarity, condition, and maker are the primary value drivers.
When did they stop making uranium glass?
U.S. commercial uranium glass production effectively stopped in 1942 when the federal government classified uranium as a strategic war material. Production resumed in 1958 after declassification. A small number of American and European manufacturers (including Fenton, Mosser, and Czech glassmakers) have produced uranium glass in limited quantities since then. Most pieces found at estate sales and antique shops are pre-1942.
Related Glassware Guides
Uranium glass collectors often also collect other vintage American glass. Explore these guides:
- Depression Glass: Complete Identification, Patterns, Colors & Value Guide
- Pink Depression Glass: Complete Pattern, Value & Identification Guide
- Carnival Glass: Complete Identification, Colors & Value Guide
- Fenton Glass: Complete Identification, Patterns & Value Guide
- Milk Glass: Complete Identification, Makers & Value Guide
- Antique Glass Collector Guide