Sweatbox - great for soaking hologram stamps!
According to Janet Klug, past president of the American Philatelic Society, in an article about working a mixture says, "You can buy or make your own sweatbox for removing paper from those stamps that should not be placed in a water bath, such as hologram stamps."
Klug says to make your own sweatbox get plastic container with a tight fitting lid and a sponge. Then put a half-inch of water in the bottom of the container. Place the sponge in the water and allow it to draw up some of the moisture. Then put the stamp on top of the sponge and put the lid on the container.
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