easy cause the 1942d Nickel is made from copper-nickel now the 1942P nickel is seen and listed as a war nickel as it has silver in it that is according to my coin book
My old Whitman folder has one of each. Would have taken a pic, but my phone wouldn't do them justice.
For those who either don't have a Red Book, or choose not to read it: In 1942, nickels struck included copper-nickel 1942 P and 1942 D, then they struck the 1942 P and S in the silver "wartime alloy" and continued to strike the silver composition up through 1945. To distinguish the silver wartime alloy, those have a large mint mark (P, D or S) above Monticello.
As an odd aside..... I often wondered why we only had one year of wartime cents and four years of wartime nickels. To my thinking, copper should be a much more necessary wartime need.
