The seven column pieces used on the project were subjected to a diagnosis of its state of conservation.
The core sandstone was in good shape, but the main problem was the loss of the decoration layer, which was plaster with a polished finish. In some places it was detached from the sandstone, presenting bubbles, cracks and fissures. In other places it was already lost, leaving the edges unprotected and about to fall. It was needed to proceed with a direct protection using a lime and sand mortar – very similar to the composition of the original layer.
After an initial mechanical cleaning to remove sand remains and other surface accumulations, a natural lime-based mortar (PLM-A® CTS) was injected inside the gaps of the stone and between the fissures in order to consolidate them. Fixing the polychrome decoration was also required, since it was fragile and dusty. For this purpose, a consolidating chemical with a calcium hydroxide base dispersed in isopropyl alcohol (Nanorestore® CTS) was applied. Once the success of the consolidations applied was tested, each of the column elements was protected individually with geotextile, leaving them ready for moving and lifting them.
The colored capital was cased within a wood box stuffed with polystyrene. Two half-moon wood covers were installed at the bottom of the capital in order to allow setting it on top of the column, while easily removing the protection. Finally, the assembled box was wrapped and secured with metal wire for extra protection when turning around the capital to its final position.