1907 Half Dollar Error List with Pictures
A Barber half struck 40% off center sold for $7,800 in 2022. That was an 1894 coin, a different-year comparison for the more dramatic errors discussed here.
Among 1907 half dollar errors, some New Orleans coins have a swollen neck nicknamed Mumps. An unworn example sold for $920 in 1997.
Estimated ranges below span $40–$10,000. Read on to compare small mint letters, surface changes, and the whole outline without mixing different examples together.
1. 1907-O Barber Half Dollar Reported Disappearing O (Estimated Up to $125)
The O looks faint or almost absent on a reported worn 1907-O. The Barber Coin Collectors’ Society survey describes this appearance but does not explain its cause.
Several things can weaken a letter. Blocked detail in the stamping tool, a weak strike, wear, or deliberate removal may look similar at first.
A nearly missing O therefore needs more than a name. The surrounding surface and any surviving curve should help explain what happened.
Remember that Philadelphia halves normally have no mint letter. A blank space below the eagle alone cannot turn a Philadelphia coin into the reported New Orleans variety.
Estimated Value
An estimated $40–$125 suits a moderately worn coin matching the report, with ordinary collectible surfaces. No automatic bonus is included just because O looks faint.
The survey records an observation, not a sale or separately priced certified error. Ordinary worn 1907-O prices provide the basis for the estimate.
Better-preserved examples need their own comparison. If someone removed the mint letter, the coin has been altered rather than gaining the reported feature’s value.
How to Identify
Look below the eagle with a 10× magnifier and move the light around the usual O position. Search for a surviving curve and compare nearby lettering for similar wear.
A scraped or lowered patch may show deliberate removal. A faint letter surrounded by sharp detail raises a different question from a coin worn evenly across its design.
Check the whole date and edge grooves. Use a digital scale and calipers when safely accessible against the normal 12.50 grams and roughly 30.6 millimeters.
A remaining O curve in an undisturbed surface gives a starting point for the reported fading letter. If no mint evidence survives, absence alone cannot establish New Orleans.
2. 1907-O Barber Half Dollar Misplaced Date (Estimated Up to $600)
A digit fragment outside the normal date can come from a misplaced punch. The Society’s survey reports this for the New Orleans 1907-O.
A worker could strike the date punch into the wrong place on the die, the steel tool that stamps coins. A part might survive after the tool was finished.
The report does not name the digit or its exact position among the border teeth. The area below the date is worth checking, but a particular shape still needs a matching example.
A date sitting slightly higher or lower is different. It does not show an extra numeral.
Estimated Value
Estimate $100–$600 for an identifiable worn example with an extra date fragment. The coin’s condition and the clarity of that fragment matter.
An ordinary 1907-O AU50 sold for $268 in March 2026. A PCGS AU53 Mumps sold listing recorded $389.99 in February 2026.
Both are almost unworn same-year comparisons, but neither is this misplaced-date variety. Their prices help frame the estimate without proving where an extra digit should appear.
How to Identify
Keep the complete date and adjoining border teeth in view before enlarging one mark. A 10× magnifier can reveal a curve or stroke that differs from the normal repeating border.
Find O below the eagle. When safely accessible, a digital scale and calipers should be compared with 12.50 grams and approximately 30.6 millimeters; inspect the edge grooves for alteration too.
Now compare the extra shape with a clearly identified 1907-O example. A cut, corrosion pit, or random raised lump does not preserve a date punch’s form.
The recognizable extra numeral is what matters. An unusually low date or one misshapen border tooth cannot establish this variety on its own.
3. 1907 Barber Half Dollar Doubled Die Reverse (Estimated Up to $800)
Check the lettering around the back, rather than starting with the eagle’s feathers. The Society lists an older description of a recut outer inscription among its 1907 Philadelphia doubled-reverse reports.
Reverse means the back of the coin. A doubled die carries altered detail in the stamping tool, which can repeat on coins made from it.
The account gives no catalog number or direction for every letter’s extra outline. Compare the shapes with a known example.
A candidate needs a consistent added shape in the outer words. Wear, flat edges from stamping movement, and reflections can also make lettering look doubled.
Estimated Value
Identifiable worn through almost unworn examples have an estimated $125–$800 range. Clear outer lettering and the Philadelphia coin’s condition determine the useful comparison.
An 1893 Barber half with a tripled back design sold for $600 in May 2025. Its stronger, separately cataloged lettering is a different variety.
That different-year sale offers a sense of price scale. It is not a transaction for the 1907 report or a promised premium for thick-looking letters.
How to Identify
Photograph the whole back inscription so neighboring letters can be compared. Under a 10× magnifier, look for an extra outline rather than a flat shelf or glare on a worn edge.
Use the same upright orientation and lighting as a known example. The old description gives no fixed direction, so upward or sideways separation cannot be required without further evidence.
Confirm a regular Philadelphia issue with no mint letter. A digital scale and calipers compare accessible coins with 12.50 grams and about 30.6 millimeters; also inspect the edge grooves.
An added contour repeated in the documented outer lettering is useful evidence. One bright, thick-looking letter is much less persuasive.
4. 1907-S Barber Half Dollar Inverted Mintmark (Estimated Up to $900)
An S changes slightly when turned upside down. Its upper and lower curves and small ends give collectors points to compare.
The Society’s survey reports an inverted S on a 1907 San Francisco half. The proposed cause is a mint-letter punch held the wrong way when entering the die.
That differs from an extra S left beside the final letter by a shifted second punch. One concerns orientation; the other concerns two positions.
Wear can flatten the details that distinguish them. Keep both the candidate and normal example upright, because turning a close-up upside down changes the apparent relationship.
Estimated Value
Use an estimated $150–$900 for a worn 1907-S with a convincingly identified inverted letter. The scarce San Francisco coin contributes much of the value.
Ordinary examples sold for $165 in Fine 12 in January 2026 and $169 in VF20 in May 2025. Those grades describe worn coins.
These sales do not measure an inverted-S premium. Another date’s recognized inverted letter also cannot supply an automatic price for the 1907 report.
How to Identify
Keep the eagle upright and place a normal same-year S beside the candidate at the same magnification. The Society’s survey records the report, while the visible letter must show the difference.
Inspect upper and lower curves and ends with a 10× magnifier. Flattening, corrosion, or a second punch remnant can change the outline without turning the original S upside down.
Check nearby metal and edge grooves for alteration. A digital scale and calipers can compare accessible coins with 12.50 grams and about 30.6 millimeters.
The reversed relationship between the S’s ends, compared in the same upright position, is the meaningful clue. A rotated photograph alone proves nothing.
5. 1907 Barber Half Dollar Repunched Mintmarks (Estimated Up to $1,200)
Part of an earlier mint letter can remain beside the final one. Punching the letter into the die again with a small shift creates what collectors call a repunched mintmark.
For 1907, the Society lists an S with extra detail above and a D with extra detail below. These are two different coins from different mints.
NGC also lists the S/S variety. The Denver entry remains a catalog report even though no example was submitted for that survey row.
A thicker-looking letter is not enough. The extra contour should preserve a recognizable piece of the appropriate earlier S or D.
Estimated Value
A damaged 1907-S/S graded ANACS Fine 15 Details sold for $74 in December 2025. Details indicates a problem that prevents an ordinary numerical grade.
Estimate $75–$1,200 across identified worn examples. Clean surfaces and clear second-letter shapes support stronger prices.
No specific Denver sale is used here. Its condition and extra D need separate comparison, rather than copying the damaged S/S coin’s price exactly.
How to Identify
With a 10× magnifier, inspect above the S or below the reported D. The extra curve should look like part of the same letter in another position.
The normal half dollar weighs 12.50 grams and measures about 30.6 millimeters. Check accessible coins with a digital scale and calipers, and inspect the edge grooves.
Return to the mint letter and look for tool cuts or added metal in the nearby flat area. NGC lists the S/S, separately from the Society’s Denver report.
A recognizable extra S above or D below is the useful match. Simple thickness or an upside-down S describes something different.
6. 1907 Barber Half Dollar Lamination (Estimated Up to $1,500)
A thin surface layer can separate and leave an uneven hollow. The year reference describes a large back-side lamination on a 1907-O graded PCGS AU55, meaning almost unworn.
It also reports Philadelphia examples. Their locations and histories should stay with their own coins rather than being combined.
Lamination begins where the metal mixture fails to hold together. A layer may remain as a flap or fall away and expose the material beneath.
Not every hollow is a split blank. Corrosion or digging can remove silver too, but neither necessarily leaves the thin-layer structure that explains this error.
Estimated Value
The year reference gives about $650 for its AU55 back-side example. It supplies no auction transaction establishing that amount.
Treat it as a reported price. An estimated $150–$1,500 covers smaller through conspicuous separation on collectible worn coins.
A large area may attract specialist interest, but damaged or unattractive surfaces still affect value. Missing metal does not automatically make a coin desirable or place it at the higher end of the range.
How to Identify
Use a 10× magnifier and angled light where intact surface meets the exposed hollow. Look for a thin separated layer rather than a uniformly gouged bowl or scattered corrosion pits.
Do not disturb a surviving flap. The O example’s report gives no clock position, so compare its actual back with the photographs instead of guessing a location.
Check the edge grooves and use calipers on accessible coins against about 30.6 millimeters. A digital scale may read below the original 12.50 grams through wear or lost silver.
Weight cannot explain the cause alone. A visible layer boundary within the metal gives the stronger distinction between lamination and a hollow made after minting.
7. 1907-O Barber Half Dollar Mumps Die Swelling (Estimated Up to $3,000)
Liberty’s neck looks fuller below her ear on Mumps examples. Stack’s Bowers described the feature on a 1907-O from the Larry H. Miller collection, graded NGC MS65.
That coin also had weak detail at the eagle’s neck and where its left wing meets the shield. Those soft areas do not identify Mumps by themselves.
The swelling is linked to a change in the die’s surface. Improper hardening has been suggested as a cause, but the exact heating history is not proved by the coin.
The visible neck shape is the place to start. Compare it with a normal portrait.
Estimated Value
An MS64 Mumps example sold for $920 at Heritage in March 1997. A PCGS AU53 sold listing recorded $389.99 in February 2026.
Estimate $250–$700 for comparable almost unworn coins. Attractive unworn MS64–MS65 examples have a separate $1,000–$3,000 range.
Both estimates include condition and surfaces as well as the neck shape. The Miller coin supplies an illustrated example, not another sale price quoted here.
How to Identify
Move a lamp across the neck below Liberty’s ear. A 10× magnifier should show smoothly stamped raised metal, not a scrape, impact dent, or attached substance.
Compare with a normal coin showing similar wear. The Miller catalog supplies a documented Mumps example.
Confirm O and inspect the edge grooves. Accessible coins can be compared on a digital scale with 12.50 grams and measured with calipers against about 30.6 millimeters.
Inspect the eagle’s neck and wing-to-shield area separately to judge how well it was struck. The matching bulge under Liberty’s ear identifies Mumps; weak back detail alone cannot do that job.
8. 1907 Barber Half Dollar Broadstrike (Estimated Up to $4,000)
The collar is a ring that normally limits how wide a coin spreads during stamping. Without its restraint, metal can move outward while still receiving the complete design.
That is a broadstrike. A wider coin with all its lettering therefore raises a different question from a design partly missing off the edge.
The year reference reports broadstrikes for 1907 without naming a mint, grade, or measured example. Those details must come from the coin.
Width alone cannot explain the cause. Rolling or flattening a finished coin can enlarge it too, but may leave different damage around the border and edge.
Estimated Value
The May 2025 specialist guide estimates Barber broadstrikes at $1,000–$2,000 in lightly worn through nearly unworn condition. Unworn examples are listed at $2,000–$4,000.
These are series estimates, not auction prices for a named 1907 coin. The amount of outward spread affects the comparison.
Complete design and original edge formation must support the error. A coin widened by later pressure belongs in a different category, regardless of its impressive size.
How to Identify
Use calipers to measure the widest and narrowest points, comparing with the normal 30.6 millimeters. Check that the complete design remains on the expanded metal.
Weigh an accessible coin against 12.50 grams on a digital scale. Spreading changes shape without removing metal, unlike grinding or trimming.
Under a 10× magnifier, inspect the wide border and edge for original stamping texture. Normal edge grooves may be interrupted or absent where the collar failed to restrain the blank.
A smooth edge alone proves little. Complete design, naturally spread metal, and an edge consistent with missing collar restraint work together to identify a broadstrike rather than a flattened finished coin.
9. 1907 Barber Half Dollar Off-Center Strike (Estimated Up to $10,000)
Some metal stays bare while part of the design runs off the opposite edge. An off-center blank entered the stamping tools too far from their intended center.
Both sides should show the same misplaced relationship. If only one border is uneven, one die may have been misaligned instead.
The 1907 year reference reports off-center strikes without a specific mint, percentage, or certification. An individual coin needs its own readable date and evidence.
A different-year photograph cannot supply those missing details. Compare the design with the metal’s outline, including the bare area, rather than judging an uneven crop of a picture.
Estimated Value
An 1894 NGC AU53 struck 40% off center sold for $7,800 in December 2022. It is a different-year sale.
For similarly substantial 1907 errors with readable dates, estimate $4,000–$10,000. The January 2025 guide puts lightly worn Barber offsets around $4,000 at 10–15%, reaching $10,000 for larger shifts.
Small offsets need lower comparisons. Neither the 40% measurement nor the auction price describes a documented 1907 specimen.
How to Identify
Find the bare area and compare it with lost or crowded design on the other side of each face. A 10× magnifier helps distinguish untouched metal from a ground-down surface.
Read the date on the coin and record any surviving mint letter. Do not assign either a mint or percentage from a similar-looking coin of another year.
A digital scale compares accessible coins with the original 12.50 grams, allowing for wear. Calipers record the outline against a normal 30.6-millimeter half, and edge photographs show changes in the remaining grooves.
Matching design displacement on both faces beside original bare metal supports an off-center blank. One uneven rim does not show the same sequence.
Conclusion
A letter’s orientation, a second letter beside it, and a faint missing-looking O ask different questions. The larger errors need the whole design and edge, while Mumps begins with the shape below Liberty’s ear.
Estimated values run from $40 to $10,000. Keep reported prices, damaged-coin sales, and different-year auctions identified clearly so a familiar nickname or dramatic photograph does not substitute for a matching coin.