Early on, regarding clay poker chips, I was told to use Vitamin E oil. I've been using it for yrears. Does nice job.
Robert
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Barbara Stanwyck blowing on dice for luck:
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Links to my gambling-related motion picture stills and lobby cards:
http://www.antiquegamblingchips.com/StillsA_TopMaleStars.htm
http://www.antiquegamblingchips.com/lobbycard.htm