Well, if its on a cent, I would say it is worth a cent. If it is on a $20 gold piece, I would say it is worth at least a grand. Since I have no idea what you are asking about though, who knows.
That's not a die crack; look into lamination issues. Value wise you are, unfortunately, not looking at much (if anything) top of what any average individual dateless might sell for.
Doesn't look like a die crack. A Buffalo, without a date, goes for $.50 at best in my area. If you have a dateless one with a die error of some kind, make it a buck.
Yeah, that's a lammy. Soak the coin in white vinegar for up to a week, checking daily. You got the mint mark, see if you can get the date or a date-partial.
