Читать книгу Monument Future - Siegfried Siegesmund - Страница 375

Knowledge of stones, historic quarries, modifications suffered in the monuments and causes of 250stone decay are necessary for conservation interventions, especially for reintegration and replacing the original stone with compatible materials.

Figure 8: PM micrograph mosaics of Montesclaros marble (M4 sample) above: parallel Nicols. A 5 mm line indicates the LMD. below: crossedNicols. A red ellipse indicates the tightly rhombohedral exfoliation in the most superficial part of the sample.

Fuente de Cibeles was originally at ground level, protected by 20 granite bollards.

All water-spouts and bollards were removed in 1862, and a perimeter cast-iron fence was installed.

The monument was moved, rotated and raised in 1895 and the rocky platform was expanded to add two putti.

A hand, the keys, the sceptre and the nose of the goddess Cybele were damaged and restored in 1931. The left lion lost its snout and suffered damage to the left front leg and tail in 1936.

The perimeter fence was removed after the Spanish Civil War and the perimeter of the fountain was landscaped. Two granite basins with cascading water from the upper basin to the new external basins were added and the flint rock covering the base of the rocky promontory was removed in 1968. The last restoration was in 2016.

The dissolution of the smaller calcite crystals that border the dolomite crystals causes increased porosity, colour change and superficial disintegration of the blasts.

Tightly rhombohedral exfoliation is in the most superficial part of the alterated sample.