I know that unbreakable crystals became available in 1916 and these replace the mineral crystal glass.
These were made of celluloid or celluloid acetate but had to be fitted to the bezel under tension.
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My question is if you want to replace one of these celluloid crystal or acrylic crystal today with a mineral glass.
What would be the procedure?
Will the glass have to be glue or is there another procedure?