Thanks for all the input. Why didn't I think of an airtight? I have like a stucko board or something painting of a riverboat and I'm mounting/gluing $1 chips from all riverboats I've played at around the perimeter of the painting. But I've already got 11 chips glued on not in an airtight, so I don't know if that will look right. The other chips are all very common current house chips so I never balked at "destroying" them by mounting them in this fashion. I even picked chips that were slightly defaced on one side and glued that side.

I'll probably use the airtight trick.

Thanks,

Cinch