Watch Crystal Mounting. A numismatic item mounted between glass crystals normally used in watches. Both sides of the item can be easily viewed, however the edge is obscured by a band which is used to hold the assemblage intact. The British were the first to do such mounting – for the first proof coins struck in 1762 for the Pitt Club (see proof surface). The band has been used for engraving, as Masonic decorations have been so made, the recipient's name engraved on the band, and a loop affixed at the top for any type suspension. In the United States cabinet medals were mounted between watch crystals in the 19th century, often in bezels when these were available. British numismatists call such a glass case a luminette. The same thin convex glass was used on one side of buttons called “watch crystal buttons.”

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X3 {1967} Luscomb, p 219.