in antiquity, properly denoted those who gave the whitening to earthen vessels, &c. In which sense they stood contradistinguished from Dealbatores, who whitened walls.

ALBARIUM opus, in the ancient building, the incrustation or covering of the roofs of houses with white plaster, made of mere lime. This is otherwise called opus album. It differed from Testorium, which is a common name given to all roofing or ceiling, including even that formed of lime and sand, or lime and marble; whereas Albarium was restrained to that made of lime alone.