I remember back in 1989 when some quarters were found with no mintmark because the die had filled in with grease. Do these types of errors have any numismatic value at all? Reason I ask is that a few years ago I found a similar quarter with no mintmark, but dated 1990. Thanks.
Not really, though there are some collectors who do collect filled die errors. They may pay a dollar or two but that's about it as a general rule.
