Portable altar made of a wooden box with a rectangular porphyry stone on the top. It is framed by gilded copper strips with an inscription inlaid in red champleve enamel which reads: PLUS VALUIT CUNCTIS IOHANNIS VOCE PRECONIS + INQUITEN(S) AGNE D(E)I TOLLIT QUI CRIMINA MUNDI + (John was stronger than all the people, saying with his herald's voice: 'O lamb of God that taketh away the sins of the world' ). Surrounding the inscription is a border of worn red velvet that undoubtedly replaced decorative metal borders.

The sides of the casket are set with relief plaques of walrus ivory:
(1) Annunciation, Nativity, Adoration of the Magi;
(2) Christ in glory with Peter, Paul, and two angels;
(3) Hand of God holding wreath supported by two angels; standing saint flanked by personifications of Sea and Earth (?);
(4) Christ in glory between two angels.

Each side is framed with an ornamental border of gilded copper strips decorated with a rosette pattern set against a backround of red champleve enamel. The claw and ball feet (repaired) are of ivory.

H. Tietze, Die Denkmale des politischen Bezirkes Melk, Österreichische Kunsttopographie 3 (Wien, 1909), 320.

A. Goldschmidt, Die Elfenbeinskulpturen aus der Zeit der karolingischen und sächsischen Kaiser VIII.-XI. Jahrhundert, Denkmäler der deutschen Kunst: 2. Sektion, Plastik ; 4. Abteilung (Berlin, 1914) vol. 2, 105, pl. 35.

K. A. Wirth, "Erde," in Reallexikon zur deutschen Kunstgeschichte 5, ed. O. Schmitt (Stuttgart, 1937), col. 997-1104, esp. col. 1076.

Arts of the Middle Ages; a Loan Exhibition, exhibition catalogue, Museum of Fine Arts Boston, February 17 to March 24, 1940, (Boston, 1940), 42, no. 124, pl. XIV.

"Dumbarton Oaks Research Library and Collection," Bulletin of the Fogg Art Museum 10.4 (1945): 108-23, fig. p. 114.

The Dumbarton Oaks Research Library and Collection of Harvard University, Handbook of the Collection, (Washington, D.C., 1946), 78-79, no. 161, fig. p. 88.

"Reawakening at Dumbarton Oaks: The Golden Glories of the Byzantine and Early Christian Worlds," Art News 45.10.1 (1946): 15-19; 57-59, esp. 58, fig. XII.

The Dumbarton Oaks Collection, Harvard University, (Washington, D.C., 1955), 109, no. 243, fig. p. 124.

Handbook of the Byzantine Collection, (Washington, D.C., 1967), 84, no. 292.

K. Weitzmann, Catalogue of the Byzantine and Early Mediaeval Antiquities in the Dumbarton Oaks Collection, vol. 3, Ivories and Steatites, (Washington, D.C., 1972), 89-93, no. 34, pl. LXII-LXVI.

H. Fillitz and M. Pippal, Schatzkunst: die Goldschmiede- und Elfenbeinarbeiten aus österreichischen Schatzkammern des Hochmittelalters, (Salzburg, 1987), no. 9.

C. Stiegemann and M. Wemhoff, Canossa 1077: Erschütterung der Welt : Geschichte, Kunst und Kultur am Aufgang der Romanik, exhibition catalogue, Museum in der Kaiserpfalz; Erzbischöfliches Diözesanmuseum, Paderborn; and Städtische Galerie am Abdinghof, July 21-Nov. 5, 2006, (München, 2006), 387-8, no. 481.

Boston, Museum of Fine Arts, "Arts of the Middle Ages," Feb. 17 - Mar. 24, 1940.

Cambridge, Fogg Museum, "A Selection of Ivories, Bronzes, Metalwork and Other Objects from the Dumbarton Oaks Collection," Nov. 15 - Dec. 31, 1945.

Paderborn, Germany, "Canossa 1077: Erschütterung der Welt. Geschichte, Kunst und Kultur am Aufgang der Romanik," July 21, 2006 - November 5, 2006.

Treasury of the Cloister (or Abbey) of Melk-on-Danube, Austria.

Purchased from Arnold Seligmann, Rey & Co., New York, by Mildred Barnes and Robert Woods Bliss, April 1937;

Collection of Mildred and Robert Woods Bliss, Washington, DC, 1937 - November 29, 1940;

Gifted to Harvard University, November 29, 1940;

Dumbarton Oaks Research Library and Collection, Byzantine Collection, Washington, D.C.