Week 11. Removing biological agents and limestone deposits

Restorers, working on the frieze on the western side, are in the process of removing all biological agents (algae and lichen) now necrotized from the stone surface by careful brushing and water.

Ammonium salt packs, prepared with deionized water and paper pulp, are applied to remove limestone deposits while thinner and less adherent limestone deposits are mechanically removed with a scalpel.