Characteristics of Ancient Mortars and Plasters from the Archaeological Site of Akbari-Serai (Pakistan)

The 17th century Mughal mortar and plaster samples were collected from Akbari-Serai (Shahdara) in the city of Lahore, Pakistan. The samples were studied employing chemical, mineralogical and micro-structural techniques consisting of X-ray diffraction, X-ray fluorescence, optical microscopy and scanning electron microscopy. The mortars and plasters were based on calcitic lime binder prepared by the calcinations of locally available lime nodules (kankar-CaCO3) from soil horizon, differing in the type and proportion of aggregates used, including crushed bricks, broken kankar pieces, brick kiln furnace slag and a small fraction of siliceous sand. The results showed varying binder aggregate ratio and also indicated different chemical composition according to the function of mortars and plasters in the masonry unit.