Mace is the outer shell of the nutmeg fruit. It has a lighter, sweeter flavour.
Should you open the small, plum-sized fruit of the nutmeg tree, inside you would find the nutmeg protectively covered by the thin, lacy-looking scarlet-coloured shell that we know as Mace. After the Mace is peeled from the shell and dried, its beautiful scarlet colour fades to a light brown. Its flavour is similar to, but more delicate than, the sturdy nutmegs. Powdered Mace is a pleasing addition (in very small quantities) to pound cake as well as to Swedish meatballs, doughnuts, stuffing, sweet potato pie, oyster stew, and barbeque sauces.
You can substitute nutmeg and Mace for each other in most recipes.