1904 Saint Louis World's Fair Wooden Postcard produced by Farran Zerbe. 

Farran Zerbe was an early-day coin dealer, promoter, and supporter of the American Numismatic Association.  In preparation for the Louisiana Purchase Centenial Expostion, the Saint Louis World's Fair of 1904, he advanced the idea that commemorative gold dollar coins should be struck by the US mint. This plan was enacted and he hawked the coins at the fair and elsewhere.  Included in his wares were some wooden postcards and other trinkets.  The example below was purchased at an auction in Colorado in the late 1980s. 

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