A type of finger ring worn by a bishop on the fourth finger of his right hand, when celebrating the Mass. Such rings were large (being worn over a glove) and were ornately decorated with severalgemstones. The earliest extant ring of this type dates from, c. 1255; another early example is the founder's ring. A bishop might have several such rings, other than a bishop, were those with officesat the Papal court.
Pontifical Ring

Pontifical Ring
A type of finger ring worn by a bishop on the fourth finger of his right hand, when celebrating the Mass. Such rings were large (being worn over a glove) and were ornately decorated with severalgemstones. The earliest extant ring of this type dates from, c. 1255; another early example is the founder's ring. A bishop might have several such rings, other than a bishop, were those with officesat the Papal court.
References
From: An Illustrated Dictionary of Jewelry, autor: Harold Newman, publishers: Thames and Hudson



