Catholic Encyclopedia (1913)/Mace
(1) A short, richly ornamented staff, often made of silver, the upper part furnished with a knob or other head-piece and decorated with a coat of arms, usually borne before eminent ecclesiastical corporations, magistrates, and academic bodies as a mark and symbol of jurisdiction.
(2) More properly, the club-shaped beaten silver stick (mazza) carried by papal mazzieri (mace-bearers), Swiss Guards (vergers), in papal chapels, at the consecration of bishops, and by the cursores apostolici (papal messengers). When in use the mace is carried on the right shoulder, with its head upwards. Formerly cardinals had mace-bearers. Mazzieri, once called servientes armorum, or halberdiers, were the bodyguard of the pope, and mazze (clavae, virgae) date back at least to the twelfth century (virgarii in chapter 40 of the Ordo of Cencius).