Japan Bead Cleaning Gone Wrong

old aurora borealis film over glass bead

I found this beautiful 1940's carnival or rainbow glass bead necklace marked Japan. I really like the J hook on this piece. (The first J hooks were used in the 1940's.)
I noticed some of the beads had what looked like a whitish dust or frost on them. Starting with the gentlest method of cleaning, I brushed with a baby toothbrush. No change in appearance. Then I dipped a q-tip in water and wiped over one of the cab beads. Oops. As I wiped, flakes came off and I could see a dark blue layer. It appears the aurora borealis coating is actually a film over a blue enamel layer over a clear glass bead.
I was being extra careful, as a few months back I had mistaken a faux pearl bracelet as being made of glass pearls. I used a q-tip dipped in rubbing alcohol to remove a few dark spots off of a couple of the beads. As I gently wiped off the spots, I smelled camphor. The sheen and depth of the faux pearls were from celluloid. They disintegrated. Chemicals destroy celluloid.
In the case of this necklace, the film coating is damaged and the frosted look is the film lifting away from the glass. It cannot be cleaned.