The three causes
A coining press has three parts that matter here: the obverse die, the reverse die, and the collar, a ring that surrounds the planchet and forms the edge. An off-center strike happens when the planchet is not fully inside the collar; the dies strike only the part of the planchet under them, leaving the rest blank. A broadstrike happens when the collar fails to rise into position at all; the planchet is centered under the dies but nothing contains it, so it spreads outward under pressure. A misaligned die strike happens when one die is out of position relative to the collar and the other die; the planchet is centered and contained, but one side's design is shifted.
How each one looks
| Feature | Off-center | Broadstrike | Misaligned die (MAD) |
|---|---|---|---|
| Design | Partial on both sides, same direction | Complete on both sides | Complete but shifted on one side, normal on the other |
| Blank area | Crescent of unstruck planchet | None | None |
| Diameter | Normal or slightly spread | Larger than normal | Normal |
| Thickness | Normal in struck area | Thinner | Normal |
| Edge | Reeding absent on unstruck part | No reeding, rim spread or absent | Normal reeding |
| Rim | Absent on unstruck part | Absent or flattened | Normal |
| Weight | Normal | Normal | Normal |
Weight is normal on all three, which is the first thing to notice: none of these is a planchet error. The planchet was correct. Something about its position or containment was wrong.
Off-center strike
The defining feature is the blank crescent: an area of the planchet that the dies never touched, showing the original planchet surface, unreeded and rimless. Both sides are affected in the same direction, because both dies struck the same displaced planchet. The struck portion is fully detailed and of normal thickness. Off-centers are described by percentage — how much of the design is missing — and by whether the date is visible, and both drive value. Estimating the percentage is its own skill. The look-alike is a coin with a section damaged or ground away, which keeps a full round outline and a full rim.
Broadstrike
The defining feature is a complete design on a coin that is too wide and too thin. With no collar, the metal spread outward, so the coin is larger in diameter than a normal example, the rim is spread flat or missing, and the edge has no reeding on reeded denominations. The design is complete and centered on both sides. Broadstrikes are valued by how dramatic the spread is and by the denomination; a broadstruck silver dollar is a very different object from a broadstruck cent. The look-alike is a coin flattened after minting in a press or roller, which distorts the design rather than leaving it complete and shows tool marks.
Misaligned die
The defining feature is that only one side is off. The collar was in place, so the coin has a normal diameter, a normal edge, and normal reeding, and the side struck by the correctly positioned die is entirely normal. The side struck by the misaligned die shows its design shifted toward one edge, with a partial blank crescent on that side only. The obverse die is the usual culprit, because it is the moving die on most presses. Misaligned die strikes are common at minor degrees and dramatic at major ones, and value tracks the degree of shift. The look-alike is an off-center strike; the difference is that an off-center affects both sides.
Check the edge first. It settles two of the three immediately.
The edge settles it
If you remember one thing, remember to turn the coin on its side. An off-center strike shows reeding on the struck portion and bare planchet on the rest. A broadstrike shows no reeding anywhere and a rim that has spread flat or vanished. A misaligned die strike shows a completely normal reeded edge, because the collar did its job. Two of the three are identified from the edge alone, and the third is identified by the edge being normal when the face is not. Sellers who photograph only the faces are leaving out the image that matters most.
Combinations
These errors combine. An off-center broadstrike is a coin struck with no collar and off-center, showing both a blank crescent and spread. A misaligned die on an off-center coin is possible. A double strike can include any of them on the second strike. Each component is diagnosed on its own terms, and a certified multi-error coin's label lists each. The error types hub covers the wider striking-error family.
Value and certification
All three are certified by the major services with the type on the label, and off-centers typically carry a percentage. Value follows drama, denomination, and date visibility, and it is found by searching the type and denomination and filtering to sold. Minor examples of all three are common and inexpensive on modern cents; major examples on silver and gold are scarce and valuable. Error coin grading and certification covers submission. Full edge photography is the image that confirms any of them in a listing.
Certified examples of all three are easy to find. Compare them side by side and the differences become second nature.
Frequently asked questions
What is the difference between off-center and broadstrike?
An off-center strike is missing part of the design on both sides and has a blank crescent. A broadstrike has the complete design but spread wider and thinner because the collar was absent.
What is a MAD coin?
A misaligned die strike: one die was off position, so one side's design is shifted while the other side is normal. The edge and diameter are normal.
Which is worth more?
It depends on degree, denomination, and date visibility. Compare sold prices for certified examples of the same type and denomination.
Can a coin be both off-center and broadstruck?
Yes. An off-center broadstrike shows a blank crescent and spread. Each error is described separately on a certification label.