"Cleaning the sarcophagus is the most irreversible part of the process," says Jessica Arista, an intern in the Walters' conservation department. "If you take something off that shouldn't have come off, you can't put it back on."
She and the other interns put in most of the 400 hours that have gone into rejuvenating the piece. The team went over the sarcophagus centimeter by centimeter, using a cleaning system based on distilled water because it contains fewer minerals. They used the "ray gun" —a machine that records the presence of trace minerals present in paint — to warn them where to proceed with extra caution to avoid dissolving lingering bits of gilt..
Then the conservators went to work with a scalpel.
"A major part of the treatment," Lauffenburger says, "is removing materials that were used previously in an attempt to restore it."
Conservators from the 19th century did the best they could. They glued the broken lid back together and plastered over the holes, occasionally obscuring the original carvings. Over time, the glue lines darkened to a brownish-yellow and stood out in sharp contrast to the more delicately colored marble.
Bit by bit, the interns chiseled away the old, brittle glue and plaster, exposing a network of cracks and chips. They then filled the chips with a new kind of glue, one that is fully reversible and mimics the texture of the rough stone surface.
"At first, we tried adding ground marble," Arista says, "but paper worked better. It looks more like marble."
Now the conservation project is in its final stage.
Arista, her hands swathed in blue plastic gloves to prevent her from inadvertently touching the piece with human, oily hands, works away at an area on the lid with a brush no wider than a penstroke. She dips the tip of her brush alternately in charcoal, brick red and chocolate, using a dabbing motion reminiscent of such pointillist painters as Georges Seurat.
"This is bigger than the brush I usually use," she says, adding that the patch being painted, perhaps 4 inches long and 2 inches wide, will take about 10 hours to complete.
"Sometimes, I do get in the groove, and then I have to stop myself from working too quickly," she says.
To a certain extent, it will be Arista's handiwork on display once the sarcophagus is finished. Her brushstrokes, her plaster carvings will replicate the cuts made in marble by the unknown master — or masters — who lived 20 centuries ago.
'You'll always be able to see the cracks up close," she says. "You should be able to see them. But if we've done our job right, when you're in the gallery and standing back a couple of feet and the lights are low, your eyes will just move past that area. You'll see the object as it was originally meant to be seen."