At your convenience, please add a close-up image of the mark on the underside.
Thank you for the images. The tray and coaster set was made by Silvers Brooklyn from Germany. These are airbrushed and date to the 1930's The set sells for $20 - $30 at auction on today's market. Here is a link for you to a set that sold for $20 and on that sold for $30:
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