I'd love to find corner pieces, like the ones on the non-Nevada mirror (BTW, that one also has cardboard backing that is smaller than the glass, like the Gem & Monte's pieces...and it doesn't seem to be glued together, though it might have been glued in its early life)

The non-Nevada pieces that are framed...the cardboard back and the glass fronts are the same sizes.

I think I'll need to add glue (or something like the stuff Archie mentioned) even if we get them framed, just to keep the pieces aligned correctly. Those corner pieces appear to be crimped on pretty tightly...I'd be afraid to put a lot of pressure on pieces that old...but I think I'll try to find something like those corners...

Thanks for your input...I hadn't even thought about those other pieces 'til you came along!