It is nothing more than a minor keystroke error, there should not be any extra value attached to it.
Quote:•Clerical errors, mechanical errors and typos are NOT guaranteed. If requested, NGC will remedy any mechanical error with respect to the description or grade of a coin on its label, free of charge. It is the duty of the buyer and seller of an NGC-certified coin to examine coins for mechanical errors and to return such coins for correction when warranted. The determination of what constitutes a mechanical error is at the sole discretion of NGC; examples of mechanical errors include, but are not limited to, the following:
â- ¦If a coin were labeled a 1955 Doubled Die
Lincoln Cent, when, in fact, the coin has no doubling, this would be a clerical error in the labeling description of the coin and not covered by the NGC Coin Grading Guarantee.
â- ¦If the coin label description references a 1916
Standing Liberty quarter, when, in fact, the coin in the holder with said label were a 1916
Barber quarter, the description would be the result of a clerical error. Once again, this would not be covered by the NGC Coin Grading Guarantee.
â- ¦If a coin were identified as a Proof, when, in fact, it is a business strike and the types are readily distinguishable from each other, this again would be a clerical error and not be covered by the NGC Coin Grading Guarantee.
â- ¦If a coin were described as an 1881-O
Morgan dollar, when, in fact, it is an 1881-S
Morgan dollar and the mintmark were improperly indentified on the label, this would constitute a clerical error, not covered by NGC's guarantee.