I have noticed a difference in Whiting marks on 2 pieces I have of Imperial Queen. Most pieces have the traditional whiting W with the griffin and than a mark that looks like an N in a circle. I have another piece of Imperial Queen that does not have this N in a circle mark. Could anyone explain this difference? Thank you. I have included pics to illustrate this difference. The first is a mark from a cold meat fork. The second is a mark from a large berry spoon with a gold washed bowl.