Reassembly—and More—Required

January 15, 2015
Index Magazine

Reassembly—and More—Required

This early 5th-century BCE kylix, a terracotta vessel decorated with illustrations of Dionysos with satyrs and maenads, was recently reassembled and restored by Tony Sigel, conservator of objects and sculpture in the Harvard Art Museums’ Straus Center for Conservation and Technical Studies.

What does it take to conserve—and reassemble—an ancient drinking cup that’s in approximately 70 pieces?

Just ask Tony Sigel, who recently completed extensive work on an early 5th-century BCE kylix, a shallow terracotta vessel decorated with illustrations of Dionysos, the Greek god of wine, and his mythological followers, satyrs and maenads.

The object had been reassembled from fragments at one point long ago, and the glue that held it together had become unstable due to age. One day, nearly twenty years ago, it simply came apart. Fortunately, “almost all of the sherds separated along old joins,” said Sigel, who is a conservator of objects and sculpture in the museums’ Straus Center for Conservation and Technical Studies. Of course, that still meant a lengthy conservation treatment involving hundreds of hours of work.

Sigel’s first step in the project was cleaning the sherds to remove old unstable fill materials, brittle, staining adhesives, and darkened paint. Next, he focused on removing a stain in the middle of the vessel, where darker pigmentation from iron had appeared (likely from within the clay itself, which naturally contains iron).

Sigel applied a poultice (a paste-like mixture) to the surface of the sherd over a period of 24 hours, which helped draw out small amounts of the rust-colored stain. After four or five applications of poultice, the sherd finally matched its surrounding surfaces.

Next, Sigel turned to reassembling the kylix—a task made even more difficult than usual by the work of previous restorers, who in earlier centuries used thick, fast-setting adhesives such as animal glues and shellac to reconstruct objects. Because they did the job hastily, the alignment was off and many sherds did not fit in the compromised reconstructions. Their solution was often simply to reshape sherds by filing them down, literally forcing each piece to align. This technique obviously did great harm to the vessel—grinding away not only edges, but also broad areas of precious surface decoration.

The kylix shape, a flat-bottomed shallow vessel on a tall foot, is particularly challenging to reassemble because its fragments are much less self-conforming than those of other, more rounded forms. Sigel used a box filled with small glass beads to prop up sherds as he positioned them together with tape, wedges, clamps, straps, and other tools. His adhesive was a thermoplastic resin, a highly stable material that is nevertheless easily re-soluble with the right solvents—meaning a future conservator could, if necessary, completely disassemble the entire kylix in acetone vapor.

After the reconstruction was complete, Sigel filled the substantial missing areas of original ceramic with plaster of Paris and acrylic spackle, all also consolidated with diluted resin.

For his last step of restoring the colors and distinctive designs of the kylix, Sigel consulted closely with Susanne Ebbinghaus, the George M.A. Hanfmann Curator of Ancient Art, and Amy Brauer, the Diane Heath Beever Curator of the Collection, both in the Division of Asian and Mediterranean Art. He inpainted, or re-created, many areas of lost design with stable, conservation-grade acrylic paints. Since the front of the kylix was to be the primary focus while the object was on display, that side was inpainted more completely than the underside. A discerning viewer can tell what is original and what is restored, because the inpainted areas are slightly lighter in tone and have a differentiated level of sheen.

After several years and much work, the kylix is now on display in the museums’ Ancient Mediterranean and Near Eastern Art gallery on Level 3. “Finally,” Sigel said, “the kylix can stand on its own one foot, as it originally did 2,500 years ago.”