Die Markers/Die Characteristics

Good question, when a coin is struck, they're struck using the same dies & will have identical characteristics/die markers.

Msaintiger, it depends on the type of marker. Most of the markers listed are some sort of microscopic damage to the die—die chips, die cracks, die scratches, die gouges, die dents. Because those die damage events happen during the minting process, the markers will be specific to a single working die.

It is important to remember that just because the die accumulates damage over usage, that does not mean all coins struck by that die will show the damage markers. Coins struck by the die before it acquired a particular gouge, scratch, crack will obviously not show those markers. Sites like Variety Vista and Copper Coins often list die state: early, middle, late, very late. You can see the damage markers accumulate over the life of the die.

As die state ages, some early markers may also be erased. For example, tiny gouges and scratches in unprotected areas may be worn smooth and indistinguishable by very late die state. Radial die flow can cover up many markers as the die surface metal shifts. In some cases, the Mint will polish damage off a working die, which can erase many markers—the 1946 5c FS-801 is a good example. Early die states had extra Monticello steps visible, but late die states appear to have either been polished or suffered enough metal fatigue that the extra steps vanished except in highly protected areas.

The final factor to consider is circulation wear. A heavily used coin can see many microscopic markers worn away. Sometimes that makes it impossible to match a coin to a listing, even if the main features seem like a good match.

Hope this helps! =)

I'm sure there have been times when dies were deliberately marked, but it's not a general thing.

In the early years, all dies were handmade and no two were exactly the same, so the markers start by relating to the slightly different positioning and structures of the design elements.

Mintmarks were hand punched into US dies until 1990 - for small population coins (such as the 1909S VDB Lincoln Cent), there are only four obverse dies used and checking those markers is an important part of verifying a coin. If the S doesn't match one of the four specific known positions, it's fake.

Today dies are created from computer-aided manufacturing and - theoretically - all start out the same. Even with CAM, there may be hand-retouching that would differ from die to die.

After they are placed in use, markers come from damage to the die that accrues in use.

The markers change over time and that lets you put them in sequence. A die chips, and then the chip grows over time (especially Cuds). This is called the emission sequence. Cuds on Coins has some samples as does VAMworld.

Then when dies are used together, this creates a marriage. Obverse Die 1 with Reverse Die B. The Liberty Seated (LSCC) and the Early American Copper (EAC) have done a lot of work in these areas. For a well studied coin, a new marriage is a major event. Reverses (which don't have a date on them) have been used many times over multiple years.