I did some checking, and the only liberty ship I can find with "Coffin" or similar spelling is the Howard E. Coffin. If this was the ship, I have some basic information here:
Built by the J.A. Jones Construction Company Shipyard in Brunswick, Georgia. The keel was laid on Nov 30, 1943, she was launched on Jan 21, 1944, and delivered on Jan 31, 1944. Her hull number was 1512.
I will e-mail you some additional information regarding the ports of call she made from her launch through 1945.
Hope this helps!