is it a collector's item?
Yes, a few were sold to the coin collecting community.
Maine Centennial half dollar
Relatively few were sold to the coin collecting community, and the majority of surviving specimens display the effects of careless handling
what is the maine centennial half dollar? It is a commemorative coin struck in 1920 by the United States Bureau of the Mint. who designed it? Harry Cochrane provided sketches, Anthony de Francisci sculpted it.
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Maine Centennial half dollar [SEP] Production, distribution, and collecting
They were sent to Maine and placed on sale through the Office of the State Treasurer at a price of $1. Thirty thousand sold immediately and they remained on sale through the treasurer's office until all fifty thousand were vended, though this did not happen until at least 1929. Bowers speculated that had the full 100,000 authorized coins been struck, most of the additional quantity would have been returned to the Mint and melted for lack of buyers. Many pieces were spent in the years after 1920 and entered circulation. Relatively few were sold to the coin collecting community, and the majority of surviving specimens display the effects of careless handling.