Processional crosses, crosiers, and shrines from the Irish medieval period were often built using an inner wooden core. Small cast parts were assembled onto the core and held in place using nails or rivets. This made it possible for the metalsmith to create large-scale religious objects without the use of a heat source during the assembly process, which alleviated the risk of heat and warpage damage to the assembled parts.
The copper alloy nails used in the building of the shrine were hand-forged to size. Cast copper alloy ingots were cut, forged, tapered and hammer hardened during the making process. The malleability of the copper alloy made it easy to form the nail into the desired shape. The nail heads could be forged to shape using a small mould made of oak or stone and finished using a variety of files. The nail heads were generally no larger than 1.5mm in diameter. St Manchan’s shrine is an exception, as much larger nails were used in keeping with its overall proportions. Apart from the use of gilding, the heads of nails were usually unadorned.
Text and photography: Kevin O'Dwyer