If you've swung a coil for more than a weekend, you already know the feeling. A clean, mid-tone signal cuts through the chatter of the ground, your pulse picks up, you cut a plug, and there it is again. A crusty aluminum pull tab. I've dug enough of them over the years to fill a few coffee cans, and for a long time I cursed every one.
Then I started paying attention to them, and they changed the way I hunt. The tab you just tossed in your trash pouch can tell you roughly when people were standing on that exact spot, how deep the good stuff is likely to be, and whether you're about to walk over a gold ring. Most folks treat pull tabs and pop tops as pure garbage. The detectorists who consistently come home with rings and silver treat them as clues.
So let me walk you through what I've learned about reading these little aluminum relics: the history that dates them, the physics that makes them mimic gold, and the field habits that turn a pouch full of trash into better finds. If you're still sorting out which machine to swing, our range of metal detectors is a good place to start.
How Beverage Cans Got Their Tabs
Stick with me on the history, because the dates are what make a tab useful in the dirt. Once you can glance at a tab and place it in a decade, you can date the ground it came out of.
Before the Tab: Flat-Tops and Cone-Tops (1935-1962)
In January 1935, the Gottfried Krueger Brewing Company of Newark, New Jersey, sold the first commercially canned beer, test-marketed about 200 miles away in Richmond, Virginia, on equipment the American Can Company practically gave them. Those early cans were nothing like the feather-light aluminum we crush today. They were heavy tinplate steel, and to open one you needed a church key: you punched a triangular hole to pour from and a second smaller hole opposite it to let air in so the beer didn't glug.
When I turn up a flat-top steel can (or a "cone-top," which had a funnel-shaped top sealed with a crown cap like a bottle), I know I'm standing on a mid-century site. There's no tab to dig nearby because the can had no opening mechanism of its own, so any loose targets around it tend to be 1930s through '50s.
Ermal Fraze and the First Pull Tab (1962-1965)
The tab we all love to hate came from Ermal C. Fraze of Dayton, Ohio. The story goes that at a 1959 family picnic he got stuck without a church key and ended up opening his beer on a car bumper. He figured there had to be a better way, and over the next few years he worked one out.
In 1962 his design got its first real-world test when his company, Dayton Reliable Tool & Manufacturing, working with Alcoa and the Pittsburgh Brewing Company, put it on Iron City Beer cans. His patent for the easy-open end issued the next year, in 1963. The mechanics are simple: a rivet anchors a ring to a pre-scored tear strip, and when you pull the ring the rivet acts as a fulcrum and the whole tab tears away from the lid. The thing spread like wildfire. By 1965 roughly 75% of U.S. breweries were using some version of it, and the soda companies weren't far behind.
The Litter Decade (1965-1975)
Convenience came with a downside that detectorists are still benefiting from. Because those early tabs came all the way off, people threw them everywhere: on the grass, in the lake, down at the beach. Through the late '60s and early '70s, billions of sharp little aluminum loops piled up across every park and swimming hole in the country. That careless decade is exactly why old gathering spots are so littered with tabs today, and why I find them stacked in layers.
The Switch to Stay-Tabs (1975 onward)
Public backlash and looming laws, most famously Oregon's landmark 1971 "Bottle Bill" (signed in 1971, in effect by October 1972), pushed the industry to keep the tab attached to the can.
- The Coors push-button (mid-1970s): around 1975 Coors ran with a "push-button" lid, two pre-scored circles you pressed down into the can, a small one to vent and a big one to drink. It solved the litter problem but nobody liked shoving a finger into their beer, and the opening was sharp. It didn't last.
- The stay-on tab (1975): the version that stuck came from Daniel F. Cudzik at Reynolds Metals, who brought it in around 1974 and saw it launched in 1975. Instead of tearing off, the ring levers a tongue down into the can. The tab never leaves.
By the early '80s the detachable tab was gone, replaced worldwide by the stay-tab we still pop today.
Identifying and Dating a Pull Tab
This is where the history earns its keep. Manufacturers changed shapes and ring styles in fairly tight windows, so the style of a tab pins down a rough date. I'm not the only one who finds this useful. There's a real volunteer project, the Pull Tab Typology of the World, that's been cataloguing these variants since 2014.
The four broad eras I run into most often:
- Zip / tear tab (1962-1965): a long teardrop ring on a pre-scored tear strip, anchored by a rivet.
- Ring-pull (1965-1970): the classic round finger ring on a wider, shorter strip.
- Beaver-tail (1968-1974): an elongated wide tail with a smaller oval loop, easier on the fingers.
- Stay-on tab (1975-present): the lever-down design that never detaches.
Here's a fuller breakdown I keep in my head when I'm trying to age a spot. Treat the dates and brands as approximate. Production overlapped and regional rollouts varied, so use them as a range, not a fingerprint.
| Tab type | Visual cues | Approx. window | Commonly associated brands | What it tells you in the dirt |
|---|---|---|---|---|
| "Zip-Top" long tab | Narrow elongated tail with a teardrop pull ring; often a jagged edge where it tore free. | 1962-1965 | Iron City, early Schlitz, Budweiser, Coors | The earliest self-opening cans. Points to mid-1960s activity. |
| "Ring-Pull" (large hole) | Circular finger ring on a wider, shorter tear strip; rivet hole centered or just above. | 1965-1970 | Coca-Cola, Pepsi, 7-Up, Pabst | The peak of the throwaway-tab era. I find these everywhere old folks gathered. |
| "Beaver-Tail" tab | Elongated wide tail with a smaller oval loop at the pulling end. | 1968-1974 | Olympia, Miller, Hamm's, Dr Pepper | Built for an easier pull. Common at old concert grounds and campsites. |
| Scalloped / notched ring | Pull ring with small ridges or scallops along the inner edge for grip. | 1970-1975 | Budweiser, Busch, regional brewers | A late variation, just before the bans. Stiff and rigid. |
| Coors push-button | Not a tab. Two pre-scored circular buttons stamped into the lid. | c. 1975-1977 | Coors | A short-lived anti-litter experiment. Mostly western states and college towns. |
| Early stay-tab ("U-tab") | Flat rectangular tab with a "U"-shaped cutout over a permanent rivet. | 1975-1980 | Early Coke / Pepsi rollouts | The transition design. Meant to stay on, but people twisted them off out of habit. |
| Modern stay-on tab | Compact rectangle with a dual-stage lever and a small oval opening. | 1980-present | Universal worldwide | Modern trash. If it's deep, the ground's been disturbed or filled. |
Why I Stopped Cursing Pull Tabs
It's hard not to get discouraged on your twentieth tab of the day. But once I understood what they were telling me, they became part of how I read a site instead of just something to grumble about.
They Date the Ground for You
In undisturbed soil, older stuff sits deeper than newer stuff. That's the law of superposition, and pull tabs give you a free chronological yardstick. When I'm working an old homestead and start pulling beaver-tails at around 3 inches, I've just established a 1970s layer. So when a faint coin signal shows up at 7 inches, I know it's sitting below that 1970s layer, which bumps the odds it's something older and worth the deeper dig. Roughly, an untouched site stacks up like this:
- Topsoil and grass: modern stay-on tabs, 1980s to now.
- Around 3 inches: vintage beaver-tails and ring pulls, 1960s to '70s.
- 6 inches and down: the pre-aluminum layer, where the silver and the relics live.
They Show You Where People Stood
Nobody drinks evenly across a park. People bunch up in the same comfortable spots, and that's where the tabs, and the lost stuff, pile up. When my tab count spikes, I slow way down, because I've almost certainly found a gathering spot:
- The shade under an old oak where people sat out the heat.
- The flat landing on a riverbank where swimmers dropped their towels.
- The sideline of a long-gone town ball field.
Where people drank, they also dug in their pockets, dropped coins, and lost rings. A heavy patch of pull tabs is usually pointing right at a heavy patch of lost valuables, which is exactly why I put so much effort into scouting good detecting locations before I ever swing.
The Pull Tab vs. Gold Problem
Here's the part that costs people gold, so it's worth understanding. It comes down to the physics of how a VLF (Very Low Frequency) detector sees metal.
What Your Detector Is Actually Reading
Your coil pushes out a magnetic field. When that field crosses a metal target, it stirs up little looping currents inside it, called eddy currents, and those throw back a signal of their own that the coil reads. The detector measures the timing of that returned signal (the phase shift) and turns it into a number on your screen: the Target ID, or VDI. Big, conductive targets like a silver coin read high, while small, low-conductivity bits like foil and iron read low.
Why Gold Hides in the Tab Range
And here's the trap. Aluminum pull tabs land in almost exactly the same VDI range as some of the best targets out there: gold jewelry, nickels, and small hammered silver.
Gold conducts well on its own, but jewelry is alloyed with copper, silver, or nickel for strength (your 10K, 14K, 18K), and that drags its number around. On top of that, a target's VDI isn't just about the metal. It's about its size, shape, and how it's lying in the ground. The result is that a vintage ring-pull can read dead-on identical to a 14K wedding band. On a typical scale:
- 0-30: foil and iron at the low end.
- 35-65: the danger zone, where nickels, small gold rings, and pull tabs all pile up together.
- 70-99: silver coins up top.
No detector on earth can reliably separate a 1968 pull tab from a gold ring on the number alone. The signals overlap too much. So if you notch out the pull-tab range to save your back, understand that you're notching out gold right along with it. (If you want to get a handle on how discrimination and notching really behave, I broke it down in our guide to notch filters and discrimination.) It's also the reason a purpose-built gold metal detector, or proper gold prospecting equipment, earns its keep when you're specifically after small jewelry or natural gold.
Reading a Target Before You Dig
The number isn't the whole story. After enough hours behind a coil, you start telling tabs and coins apart by ear and by behavior, well before the shovel comes out.
Listen to the Shape
A coin or a ring is round and compact, so it gives you a crisp, tight tone that sounds the same no matter which way you swing. A pull tab is flat and lopsided (an open loop on one end, a thin tail on the other), and that uneven shape gives a wider, sloppier signal. To my ear a tab often sounds a touch hollow or stretched, or breaks up at the edges instead of giving that clean, solid pop.
The 90-Degree Cross-Swing
This is the oldest trick in the book and I still use it constantly:
- Swing over the target and note the number and how clean it sounds.
- Step around 90 degrees and swing over it again.
- Watch what the signal does.
A round coin won't care. It holds its number from any angle. A pull tab usually doesn't hold up: the VDI jumps a few numbers or the tone breaks apart, because the tab's long, uneven shape reads differently across the coil from the new direction.
Let Multi-Frequency Help
Newer detectors run several frequencies at once and read the target on all of them together, which gives a fuller picture than any single frequency can. A single-frequency machine (say 14 kHz) hands you one averaged number. A simultaneous multi-frequency platform, like Minelab's Multi-IQ running roughly 5/10/20/40 kHz at the same time, gives more data to work with, and can sometimes catch the hollow middle of a ring-pull versus the solid mass of a coin.
Sizing a Target with Your Pinpointer
One more read I take before committing to a dig is the target's apparent size, using the detector's pinpoint mode.
Most decent machines have a non-motion pinpoint that scales the audio to how strong the signal is. Drag the center of the coil slowly across the target and feel out its edges:
- Coins give a tight peak that drops off fast inside a 1-2 inch circle.
- Whole cans stay loud across 5 inches or more. That's a deep can, not a shallow coin, and usually not worth the crater.
- Pull tabs read a little stretched out, mirroring the inch-and-a-half length of a vintage tab.
A good handheld pinpointer makes this quicker and far more precise once you're down in the hole.
Reading the Brand on the Tab
If you really want to nerd out, the tab's design can hint at which brewer it came from, and that adds color to a site's story. A few I recognize on sight (again, dates are rough ranges):
Coors
Coors liked to do its own thing. Around 1975 it pushed the push-button lid to fight litter, those two pressed-in circles. When I find push-button tops, I'm usually looking at a site that was active between 1975 and 1977, and a crowd that drank western regional beer.
Anheuser-Busch (Budweiser)
Bud ran classic large-loop ring pulls through the late '60s, with generous finger holes and good aluminum. Because it was everywhere, finding a pile of these is a solid sign of general public activity: a popular picnic ground, a party spot, a gathering place.
Schlitz
Schlitz liked stiff, heavily built tabs, sometimes with a cross-bar across the ring so it wouldn't snap before the strip opened. A Schlitz flat-bar tab usually puts me in the late '60s to very early '70s.
Using Tabs to Date a Whole Site
Archaeologists treat modern junk with the same respect they give old pottery, and pull tabs happen to be a tidy way to date a site's layers.
There's a legitimate method called Mean Ceramic Dating (Stanley South came up with it) where you estimate when a site was occupied by averaging the median production dates of the pottery types you find. You can borrow the same idea informally for a 20th-century spot using pull tabs. It's not an official, named technique (think of it as a back-of-the-napkin version), but the logic is sound: because tab types were made in known windows, averaging them tells you roughly when an area saw the most foot traffic.
The math, loosely: your estimated peak date is the sum of (how many of each tab type you found times that type's median year), divided by the total number of tabs.
Say a park gives up 45 zip-tops (median around 1963) and 120 beaver-tails (median around 1971). Run the average and you land squarely in the late 1960s, which tells you where to focus your deeper, slower passes.
Do Right by the Tabs You Dig
Every one of us is an ambassador for the hobby whether we like it or not, and how we handle trash (tabs included) decides whether the next detectorist gets permission to hunt that park at all.
Dig It All
The hunters I know who pull the most gold all share one habit: they dig everything. Yes, it's a grind to recover dozens of tabs in a session. But it's the only way to be sure you didn't just walk past a ring. And every scrap of aluminum you take out leaves the ground cleaner and your next pass quieter, with a better shot at the deep, old stuff.
Leave It Better Than You Found It
- Use a drop cloth. Pile your dug soil on a small towel so it pours back in clean instead of scattering across the grass.
- Cut a proper plug. Use a sharp tool to cut a U-shaped plug with one side still hinged at the roots, fold it back, grab the target, fold it home, and step it down firm. A good digging tool or shovel makes a clean plug effortless, and down at the water a sand scoop does it in one scoop.
- Pack it out. Don't toss a tab back in the hole or leave it on a fence post. Carry a trash pouch and take every piece home. It protects the ground and keeps these spots open to us.
Frequently Asked Questions
What is a pull tab?
It's the original self-opening mechanism on a beverage can, a little aluminum ring and tear strip that came right off the lid when you pulled it. It showed up commercially in 1962 and was mostly replaced by the non-detachable "stay-on tab" after 1975.
Who invented the pull tab, and when?
Ermal C. Fraze of Dayton, Ohio. He worked it out in the early 1960s. It first hit shelves on Iron City Beer in 1962, and his patent for the easy-open can end issued in 1963.
What year did pop tops change to the modern tab?
The detachable tab started giving way to Daniel Cudzik's stay-on tab in 1975, and by the early 1980s the modern non-detachable tab had taken over everywhere.
Are old pull tabs worth anything?
Mostly just scrap-aluminum value. But to us they're worth plenty as dating tools (the style tells you when a site was active), and a few rare brewery variants do draw modest collector interest.
Why do pull tabs read like gold on a metal detector?
Because a small gold ring and an aluminum tab are close in size, shape, and conductivity, so they land in the same mid-range VDI band (roughly 35-65 on a lot of machines). Notch out the "pull tab" numbers and you notch out gold too.
How can I tell a pull tab from a gold ring without digging?
You usually can't be sure. That's why we dig the whole range. But the tells that lean "tab" are an erratic or hollow tone, a number that jumps when you cross-swing 90 degrees, and a slightly stretched-out pinpoint. When in doubt, dig it.
Sources & Further Reading
- Ermal C. Fraze and the pull-tab can (Wikipedia, with cited primary sources).
- "Beer Cans: A Guide for the Archaeologist", on can-end typology and dating.
- Pull Tab Typology of the World: contemporary-archaeology tab classification.
- Oregon Encyclopedia: the 1971 Beverage Container Act ("Bottle Bill").
- U.S. patent records: Ermal C. Fraze (pull-tab, 1963) and Daniel F. Cudzik / Reynolds Metals (stay-tab, 1975).
Got a tab you can't place? Toss it in your finds box and compare it against the table above after your next hunt, and you'll start dating your sites without even thinking about it.
