Will this coin holder?

It doesn't look like environmental damage; it looks like haze combined with toning. Heavy haze like that will probably be a grade-limiting factor, but should not make it a details coin. My guess is the toning is natural, although a bit unusual looking. It's possible that some graders could see it as artificial, however.

@Samets said:

@IkesT said:
It doesn't look like environmental damage; it looks like haze combined with toning. Heavy haze like that will probably be a grade-limiting factor, but should not make it a details coin. My guess is the toning is natural, although a bit unusual looking. It's possible that some graders could see it as artificial, however.

Thanks for your opinion. I'm debating if it's worth the money to take a chance on sending it in...

You're welcome. If getting a better grade is your goal, there is a good chance that the haze could be removed with a chemical treatment. There are a couple of options, but both would likely remove the toning as well. If you like the look of the coin as is, I wouldn't attempt any treatments.