Here is a fantastic medium clear glass button with a metal deposit decorative finish, applied to the glass surface by way of electric current. Metal deposits made in this way can be very thin, or thick enough for engraving. For a thorough discussion of the process, see the October 2003 National Button Bulletin. Silver, gold and copper have been applied to our buttons since the process was first patented in 1889.
The above is based on the National Button Society's Classification System.
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