I can't even find a record of buying it, though I seem to remember getting it cheaply. Diameter is about 24.5 mm or 1", weight is 1.2 grams, material appears to be aluminum. What I can read of the letters seems to be "UNION TRUST CARTHAGE MO, ONE TRAY, and the big C.S.A. stamped on both sides. Could this possibly be a Confederate States of America token?
Aluminium was not in general use till 60 or 70 years after the Civil War. Some one has taken a big old punch and whacked the token, which itself probably dates from the 1920s or 1930s. One Tray may make it a field labour token, handed out for picking one tray of produce, redeemed for cash at the end of the work period.
A little Googling turned up this from the Missouri Journal of Numismatics: https://archive.org/stream/missourijournalo0004miss/missourijournalo0004miss_djvu.txt Scroll down that page a bit to the article "Missouri Strawberry Tokens" by Michael Pfefferkorn. He dates the tokens to c.1895-1925, and gives more background about the history of strawberry growing in Missouri than you probably wanted.
Great work! Thanks! That link explains it very well. "The Union Trust Company was organized c. 1913 and was in business as late as 1931. In 1914, J. H. Staley was president and J. C. Wyatt was secretary. By 1931, the officers were J. D. Harris, president, and Charley L. Bollinger, secretary. All of the Union Trust Co. one tray tokens have been counterstamped C S A which stands for Carthage Strawberry Association. Apparently, the Union Trust Co. went under during the Depression. The strawberry grower’s association may have then taken over the responsibility of handling the tokens. It is possible the change occurred in the mid-20’s after Treasury Department opposition to bank issuance of a monetary token. This counterstamp is frequently misinterpreted as standing for the Confederate States of America."
