Antique Sanctus bells

“An altar bell (also Mass bell, sacring bell, Sacryn bell, saints' bell, sance-bell, or sanctus bell) is typically a small hand-held bell or set of bells. The primary reason for the use of such bells is to create a "joyful noise to the Lord" as a way to give thanks for the miracle taking place atop the altar.^[1]” 

^{one of three bell is missing its “clapper”}