1920 Half Dollar Error List with Pictures
A Walking Liberty half dollar struck twice sold for $11,400 at Heritage in August 2025. It was an undated San Francisco coin, so the result is a series comparison rather than a 1920 sale.
Estimated values for the 1920 half dollar errors considered here range from $75 to $15,000. They cover incomplete blanks, repeated designs, and displaced or repeated strikes.
Read on to learn what each candidate must show before an auction comparison can help value it.
1. 1920 Walking Liberty Half Dollar Clipped Planchet Error (Estimated Up to $350)
A missing piece at the edge can begin before the coin is struck. The machine that punches metal blanks from a silver strip may overlap an earlier hole, leaving a curved gap.
A strip edge can leave a straight or irregular missing section. The incomplete blank then receives the coin design around that gap.
Collectors call this a clipped planchet; planchet means the metal blank prepared for striking. It differs from cutting a piece from a finished coin.
For a 1920 candidate, inspect both faces and keep the date visible. A neat cutout alone does not prove a mint error.
Estimated Value
A 1942-S rim clip graded ANACS MS62 sold for $81.90 including fees in May 2025. MS62 describes an unworn coin with noticeable surface marks.
That later Walking Liberty comparison supports an estimated $75–$350 for a 1920 candidate. It is not a recorded 1920 sale.
The clip’s size, clear original surfaces, and the normal value of the coin’s mint and condition affect the range. A small rim nick is a different problem.
How to Identify
Inspect the gap with a 10× magnifier and low side lighting. Saw marks, fresh sharp edges, or crushed nearby letters can reveal work done after striking.
A digital scale should show less than the normal 12.50 grams, consistent with the missing metal and wear. Calipers may still read about 30.6 millimeters across an undamaged part.
Look at the rim opposite the gap for supporting weakness. Collectors call that the Blakesley effect, but its absence or presence is not a complete test by itself.
Original-looking edge texture joined to undisturbed design on both faces is the clearest first distinction from a cut-up finished coin.
2. 1920 Walking Liberty Half Dollar Doubled Die Reverse (Estimated Up to $2,200)
An extra rounded stroke on a back letter may indicate a doubled die. A die is the steel tool that stamps the design onto the coin.
If that tool already carries repeated detail, the struck coin can copy it. A slipping tool during one strike can leave flat ledges instead.
HALF DOLLAR and the eagle are places to inspect a 1920 candidate, not confirmed markers of a named variety. The well-known 1946 doubled back shows the general kind of error.
That later coin cannot identify a 1920 example. The actual extra shape must be checked on this year’s coin.
Estimated Value
A 1946 DDR FS-801 graded NGC MS65 sold for $2,040 at Heritage in November 2024. That is a recognized later variety in a high unworn grade.
Use an estimated $100–$2,200 for an identified 1920 candidate, depending on condition and clear repeated back detail. The older comparison guides the upper end.
It does not establish a 1920 auction result. Flat ledges caused during striking should not receive the price comparison for a doubled tool.
How to Identify
Set a normal Walking Liberty back beside the candidate at equal size. Choose one actual extra stroke or repeated junction, rather than judging how busy the eagle looks.
Use a 10× magnifier and change the light direction. A flat ledge beside a narrowed main letter suggests movement during striking, while a reflection may vanish as the light moves.
The front must show 1920; record any mintmark on the back too. A scale and calipers check the normal 12.50 grams and 30.6 millimeters.
A stable repeated feature with the same raised character as the surrounding design is the evidence to establish first, without borrowing the 1946 variety’s name.
3. 1920 Walking Liberty Half Dollar Doubled Die Obverse (Estimated Up to $2,500)
Two outlines can come from a doubled tool or from a coin struck twice. For a doubled die, the repeated shape was in the tool before the coin was made.
Obverse means the front. The date and lettering offer practical places to examine a 1920 candidate.
No particular direction of doubling or mint is established by this general entry. A normal-looking part of the portrait can sit beside a genuine local feature.
Wear makes the judgment harder by softening raised detail. A shadow in a large photograph is less useful than an extra shape that remains visible as lighting changes.
Estimated Value
A 1939-D DDO FS-101 graded NGC MS67+ brought $2,160 at Stack’s Bowers in April 2025. Its exceptional unworn condition makes it a strong comparison, not a routine doubled-letter price.
An estimated $100–$2,500 applies to an identified 1920 candidate across different conditions. The range depends on genuine repeated design and the coin’s normal value.
The cited sale remains a 1939-D result. It does not establish that a 1920 coin has the same pattern or value.
How to Identify
Follow a suspicious letter from the main stroke into its extra outline with a 10× magnifier. The two parts should form a sensible repeated shape, not merely a low flat ledge.
Inspect nearby details as well. Not every part of the portrait must repeat, but the visible pattern should remain consistent.
Compare a normal 1920 front under the same lighting. Glare on worn silver can suggest an extra edge that is not actually metal.
The standard half is 90% silver with a ridged edge, weighing 12.50 grams and measuring about 30.6 millimeters with a scale and calipers. Rounded separation or a real notch gives the clearest starting evidence.
4. 1920 Walking Liberty Half Dollar Off-Center Strike Error (Estimated Up to $12,000)
Part of Liberty or the lettering can disappear beyond the edge while a blank crescent remains opposite. That combination is the visible result of an off-center strike.
The metal blank sat partly outside the stamping tools. Metal beyond their reach stayed untouched, while some intended design missed the blank.
The coin may still have its normal weight because the missing part is design, not necessarily silver. That differs from a clip with metal absent.
A readable 1920 date is essential for this year’s comparison. A wide rim or a dramatic undated example cannot establish the date by itself.
Estimated Value
A 1918 Walking Liberty struck ten percent off-center sold for $10,575 at Heritage in April 2013. PCGS graded it MS65, a well-preserved unworn level.
That historical same-series sale supports an estimated $3,000–$12,000 for a 1920 candidate. A readable date, surface condition, and a clear shifted strike all matter.
The range is not set by percentage alone. The 1918 result also does not prove that an authenticated 1920 example is known.
How to Identify
Trace the design around both faces and note where it runs off the edge. Photograph the blank crescent with the adjacent rim and surviving date still visible.
If all design remains, investigate a widened strike instead. If only the front shifts while the back stays centered, a misaligned stamping tool may explain it.
A 10× magnifier helps separate untouched blank metal from grinding that removed existing design. Record weight with a scale against 12.50 grams and the outline with calipers against the usual 30.6 millimeters.
The key first check joins three things: readable 1920, matching design loss, and genuinely unstamped metal on the same coin.
5. 1920 Walking Liberty Half Dollar Double-Strike Error (Estimated Up to $15,000)
Two sets of design can overlap when a coin stays in the press and receives another strike. If the coin moves between blows, the second impression lands in a different position.
Large details and rims can show that movement better than tiny letters. Parts of the first design may survive beside or beneath the second.
The result depends on how the coin moved and which areas were struck again. It is not the same as a repeated design already present in one stamping tool.
A 1920 candidate must demonstrate this relationship. An example from another year explains the process only.
Estimated Value
An undated San Francisco Walking Liberty double strike brought $11,400 at Heritage in August 2025. PCGS graded it AU53, with light wear; the second strike was ninety percent off-center.
Estimate $5,000–$15,000 for a substantial, authenticated 1920 double strike. That is a comparison-based range, not a recorded sale of a 1920 coin.
Readable dating and the arrangement of both impressions matter. The undated comparison’s ninety-percent shift is not a required feature of a 1920 example.
How to Identify
Begin with a large surviving feature and trace each impression separately. Check how the two designs, rims, and blank areas fit together.
Through a 10× magnifier, look for places where the second blow flattened or covered the first design. Marks from squeezing finished coins together can be sunken and mirror-imaged instead.
Inspect both faces, the readable date, and any mintmark. A digital scale and calipers record measurements against the normal 12.50 grams and 30.6 millimeters, although the outline may have changed.
A doubled tool does not require the coin to move between two blows. Two compatible sets of strike-made detail, rather than one repeated edge, provide the direct starting test.
Conclusion
The estimated $75–$15,000 range covers several different 1920 candidates. Missing metal points toward a clip, repeated design may come from a doubled tool, and displaced or overlapping impressions need a striking-error check.
The quoted auctions involve explicitly identified comparison coins, including other dates and an undated example. Match the actual feature and condition before applying a range, keeping a readable 1920 date central to this year’s identification.