How can you tell? 1 1

[Tonya1821]

What is the best way of telling the difference between an error and circulation mark? I have a bicentennial that looks like it has an error below the drum above the o in dollar but I can’t find anything like it?

[Sandon]

   Welcome to the NGC chat board.

   If possible, please try to provide clearer images of both sides of the coin, cropped like this to eliminate the surrounding surface:

   Based on the current image, the raised area above the "O" in "DOLLAR" appears to be from a die chip, which is regarded as a product of normal die wear or a quality control issue rather than a mint error. Coins with die chips are sometimes collected by new or casual collectors as novelties but generally aren't worth much if any premium and aren't attributed as mint errors by third-party grading services such as NGC. 

   To attempt to answer your question, a nick or other mark on a coin from bag storage or circulation would be mostly a depressed area of disturbed metal, with some raised displaced metal at its edges. The topic of mint errors is an advanced one that requires more basic knowledge about coins and especially knowledge of how they are made. There are many different kinds of mint errors that differ widely in appearance and even more kinds of damage that a coin can suffer after it is struck. It is extremely unusual to find any significant error coin in circulation.

  If you are a new collector who wants to know more about U.S. coins and how to collect them, please so inform us so that we can direct you to appropriate basic resources. For some introductory information about mint errors, please see the following:

Learn Grading: What Is a Mint Error? — Part 1 | NGC (ngccoin.com)

Learn Grading: What Is a Mint Error? — Part 2 | NGC (ngccoin.com)

Learn Grading: What Is a Mint Error? — Part 3 | NGC (ngccoin.com)

Learn Grading: What Is a Mint Error? — Part 4 | NGC (ngccoin.com)

The site error-ref.com provides more comprehensive information about mint errors.

[JKK]

Start by assuming they are all circulation marks. That is the automatic presumption and the challenge, the burden is to prove that such a mark somehow happened at a mint.

To use a judicial analogy, assume that the prosecution has video conclusively identifying the accused in the act of committing the crime, and that your task is to prove the accused innocent. That's how skewed it is. If you do that, you will be looking at this sensibly and will not be starting out with false hope, but with healthy skepticism. That's the best help I can offer you.