In Thanjavur (Tamil Nadu) a single family preserves an individual school of painting which, whilst integrating foreign elements, continues an old tradition expressed in an original technique. Thin cardboard is glued onto a board of pilla wood, and over this a sheet of calico. On this surface a paste of gum made from ground tamarind seeds and powdered stone is spread. When this is dry the outline of a picture is sketched in crayon. It is characteristic of these paintings that decorative materials are used to embellish them - in the very best work gold leaf and semi-precious stones may be used but, more commonly, these are replaced by foil and coloured glass. The gold leaf or foil is glued over selected parts of the sketch, followed by the real or imitation gems. It is only at this stage that painting begins, using strong primary colours and starting with the background. Finally, the main figures are added and the details completed. Today the hand-ground natural colours have been religiously replaced by factory-produced pigments.