48 pieces: Reassembly of an Ancient Greek marble lion using an internal armature with reversible mechanical components

Joe Rogers and Dale Benson

Abstract

Purchased for the 1933 opening of The Nelson-Atkins Museum of Art in Kansas City, Missouri, the Attic Lion is considered one of the finest sculptures in the Museum’s antiquities collection. Carved from white Pentelic marble, the sculpture was used as a funerary object to protect the dead and stands an impressive 46 inches in height, 82 inches in length and weighs 3,006 pounds. Dating to 325 B.C., the life-size sculpture arrived in Kansas City after being “repaired” from recently found fragments near Athens. Unfortunately, during a gallery renovation in 1993, it was discovered that large sections of the sculpture were beginning to separate. After careful examination and extensive gamma-radiography, it was determined that internal pressure from corroding iron supports held with plaster of Paris used in the previous restoration was contributing to the problem. A complete disassembly of the 48 pieces was necessary to stabilize the sculpture by removing iron supports.

Key objectives of the treatment were: disassemble the sculpture and remove the corroding internal iron armature used in the previous restoration; develop an internal stainless steel armature to hold the three largest fragments of the sculpture together using compression forces rather than difficult to reverse structural adhesives, avoid drilling new holes; and eliminate an external, visually obtrusive mount that ran from the torso to the base. Most importantly all the new repairs should be as reversible as possible. With the assistance of a mechanical engineer a unique, adjustable, reversible armature incorporating compression cramps and threaded tie bars was developed to bring the stone surfaces together for maximum surface to surface contact. Even with fragments weighing in excess of 1,100 lbs, the internal armature and adhesive now support the massive amount of weight, offering tremendous shear and tensile strength.

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