I have also finished my 2 mini copper and glass books from the Art Retreat in Las Vegas last week, the Thomas Ashman class.
Inland Border Security (US) saw fit to riffle through my luggage, which is only fair considering the quantity of paint, gesso, Golden gel medium I was bringing back. And my little books must have looked ominous on their scans. I just wish they had bothered to repack the books as carefully as I had put them, wrapped in bubble pack and paper towels. But I guess it's not their job, so the glass was broken, and a mess it made.
It was my opportunity to try a different method, since I'd had such an awful time (close to undoing me...) fitting the glass inside the copper tape. On one book, I used a transparency with a back, on another I used just a plain photo. That will work for me.