INVESTIGATION OF MORTAR AND STONE DETERIORATION IN THE VICTORIA MEMORIAL, CALCUTTA

The impressive Italian Renaissance architecture in Calcutta known as t he Victoria Memorial has deteriorated noticeably over the last decade. As this has become a major cause of concern, a detailed microstructur al investigation of the damaged parts was undertaken to establish the cause of deterioration. This study shows that protracted absorption of pollutants and hydratable salts has given rise to crystallization dam age to the sandstone; the carrier substance is moisture. Separation of mortar joints has also occurred, and biological activity has resulted in the deposition of black and greenish patinas on the marble exterio r and mortar joints. Copious deep-green patinas of copper sulfate have developed in places where copper plates were used within the structur e, causing the building considerable loss of aesthetic beauty.