The nutmeg tree (Myristica fragrans) is a tropical evergreen that produces both nutmeg and mace. Red Mace is the red lacy coating (called the aril) that encases the nutmeg seed. When the tree's fruit reaches maturity, it splits open and reveals the aril and seed. The fruit is harvested and the aril is removed by hand, flattened, and left to dry outside for 10 to 14 days. The red aril takes on an amber-, yellow- or orange-brown color as it dries and, when left whole, is called a "blade" of mace. The blades are sold as is or processed into a ground spice.
