Specimens are selected from the finished coin and are put into a box or " pyx."
They are probably of the Norman period, and were kept in the Pyx Chapel at Westminster, now in the custody of the Commissioners of Works.
It was reserved in a closed vessel, which took various forms from time to time, known in the East as the aproc 6ptov, and in the West as the turris, the capsa, and later on as the pyx.
In the East it was kept against the wall behind the altar; in the West, in a locked aumbry in some part of the church, or (as in England and France) in a pyx made in the form of a dove and suspended over the altar.
From the eastern walk a porch gives entry to the chapter house and the chapel of the Pyx.