Was going through a lot of Buffalos and got this. I was wondering if it is just die deterioration or is it a actual doubling error.
Hard to tell from partial pictures and the wear. Here is a link for 1937: http://varietyvista.com/03 Buffalo Nickels/DDO 1937.htm
Unfortunately it appears to be a worn die struck coin that became a worn coin. I don’t know of any DDOs for a 1937-D. JMHO