Actually, there have been two US coins with shells. They were both
circulating commemorative coins from the thirties: the 1936 Norfolk,
Virginea Bicentennial half-dollar shows two scallop shells on the obverse,
and the 1935 Hudson, New York half-dollar depicts a mermaid blowing a
stylized triton's trumpet in the background behind Neptune who is on the
back of a whale. Both these coins generally sell for several hundred
dollars each.
John Jacobs
Seffner, FL
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