Prior to salt removal, the deteriorated stone required temporary consolidation and stabilization. Salts were then removed from the stone with a paper pulp poultice and immobilized with barium hydroxide, after which grout injections were made to reattach delaminating stone. Research revealed a 1950's application of a silicone cement-based water repellent that had darkened the stone surface; low pressure micro-abrasion safely removed this coating. After cleaning, fragile stone was reattached with ceramic pins and adhesive. Cement patches were removed and cracks and open losses were filled with a hydraulic lime mortar, colored to match the stone.

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