Restoring the Ruin
Mating two pieces
When it's time to fit a newly
fashioned piece of marble with a broken or irregularly shaped
ancient one, the team once again borrows from Periclean times. To
ensure that the new piece exactly snuggles against the old, they
coat the inner surface of the new marble with red clay. They gently
push the two pieces together, then pull them apart. Points on the
new piece that turn white—that is, where the clay is scraped
off—indicate spots on the new slab that need fine-tuning. The
operation is repeated dozens of times until the new marble precisely
matches the ancient surface.