Whole blade mace (US$10.99/lb) is also available online from the Spice House (1512 North Wells St, Chicago, IL 60610, tel 312-274-0378). What is blade mace? Mace is the lacy, reddish, outer-covering (the aril ) of the nutmeg (Myristica fragrans) seed. “Should you open the small, plum-sized fruit of the nutmeg tree,