Traditional Use of Organic Additives (Bamboo Foliage, Flax Fibre and Millet Grains) in 16th Century Lime Plaster of Solapur Fort, India

Abstract

This paper reports the characterization of organic and inorganic additives from the 16^th century Western Indian Fort of Solapur. The analytical investigations were performed by means of petrographic thin section, granulometric analysis, XRF, XRD, FTIR, SEM-EDX, and DTA/TGA. The studies indicated the presence of the polymorphs of calcite and inclusion of clay minerals i.e. illite and vermiculite in one sample of the plasters. Calcite rich air-lime showed the presence of essential minerals likes quartz, feldspar, biotite and lime component. Observations under SEM, light microscopy and Polarized microscopy revealed inclusions of Bamboo foliage, Millet grains and Flax fibres as organic additives in the plaster as reinforcement. Although the use of Bamboo culm in construction has adequately been reported, for the first instance bamboo foliage was evidenced in plasterworks of Solapur fort. The high silica content of bamboo foliage probably helped in providing strength to the plaster. The inclusion of millet grains has provided thermal, gelatinization and hydration properties to the plasters. The stronger, crisper and stiffer flax fibres gave thermal and elastic properties to the Solapur plasterworks.