It was considerably reworked between the 13th and 15th centuries and became a cumdach or "book shrine", when its basic timber structure was reinforced and decorated by elaborate silver-gilt metalwork.

Its front cover was enhanced by gilded relief showing Jesus in "Arma Christi" (with Instruments of the Passion), alongside depictions of saints, angels, and clerics, in scenes imbued with complex iconography.

And the Saint then left Bishop Mac Carthainn there, at Clogher, and bestowed the Domhnach Airgid upon him, which had been given to Patrick from heaven, when he was on the sea, coming to Erin.

[13] It is traditionally associated with Patrick and believed to have been in his possession and sanctified by him[4] before he presented or gave it to St Macartan (454—506), the first Bishop of Clogher diocese in southwest Ulster.

[14][15] The original casket may have been referred to in the 10th century "Tripartite Life of St Patrick", which mentions gifts made to him, including relics of the Apostles, portions of the True Cross, and tufts of Mary's hair, or the Holy Sepulchre.

[17] The work was completed by the Clones craftsman and goldsmith John (Eoin) Ó'Bárdáin, whose signature (IOHANES: O BARRDAN: FABRICAVIT) is engraved on the shrine.

[18][9] Ó'Bárdáin is known to have lived in Drogheda,[19] and modernised its appearance in the contemporary International Gothic style, including the covering of the earlier wood shrine with tin-lined bronze panels decorated with interlace knots.

[23][24] The four panels around Jesus contain eleven smaller, ornately and delicately figures carved in low-relief (basso-rilievo),[12][25] They depict saints and clerics dressed in clothes that draw from both early medieval Irish and European gothic styles.

[17][20] The upper left-hand panel shows the Archangel Michael and the Virgin and Child depicted in the Nursing Madonna (Virgo Lactans) style.

[3] A number of other figures, including running animals and zoomorphic grotesques, some with unusually large jaws and bulbous eyes, were placed on small mounts at the borders and corners of the front cover.

[29][36] In 1918, Edmund Armstrong and H. J. Lawlor provided in-depth descriptions and accounts of its symbolism and provenance for the Clogher Diocesan Register, and their work is still considered largely definitive.

[33][31] This took place during a period of refocus and acquisition by the Academy (as they put it, "judicious purchasing"), in part influenced by the antiquities dealer Redmond Anthony's (1768-1848) collection of Irish medieval jewelry and decorative artworks.

[11][38] The museum's new directive sought to bring from private to public collections works of national historical significance such the Cross of Cong (a donation from 1839) and the Ardagh Hoard (acquired 1874), that had languished as mere curiosity pieces.

Areas of the gilding contain accumulations of dirt, and any colourisation has long since faded, leading to its current dark appearance of mostly brown and black hues.