Mace The nutmeg tree, Myristica fragrans, is special in that it produces two separate spices, nutmeg and Mace. Mace is the ground outer covering (aril) of the nutmeg seed. A piece of unground Mace is called a blade. In its natural state, mace is a bright crimson lace up to 35 mm (1-1/2 in) long, encasing the brown nutmeg in irregular, fleshy lobes. As it is dried, it develops its characteristic aroma but loses its bright red color. The mace can become brittle and horny, though the best quality mace will retain some pliability and release a little oil when squeezed. It grows in Indonesia (Siaw-Ambon and Papua islands).