History of Technology in India, Vol. I: From Antiquity to c. 1200 A.D. v1.c13.s3.8

v1.c13.s3.8

Another example of the skill of the ancient Indian is the process of casting of bronze coins. For producing these cast coin, as described by Sharma and Bhardwaj (1987) and Mukherjee and Lee (1988), the impression of a number of coins was made on Terracotta disks as shown in Fig. 52 with a central sprue connected to all the molds by small runners. The cope and drag of these disks were stacked to form a ‘Jhari’ type mold. This stack was carefully packed from all the sides in a sand molding box and then molten metal was poured through the central sprue. As the 1. Wax model of the deity is prepared. The core is made of clay and sand.
2. The wax model is covered with clay.
3. Preparing the mould with the heating wick on.
4. The next stage is heating the mould to drain the wax and baking the mould in sand.
5. Pouring molten metal into the wax emptied mould. After cooling the mould is broken.
6. And the result comes to light with the master's touch.