The basis on which archaeologists identify the centres of craft production are :
- Raw materials such as stone nodules, whole shells, copper ore, etc.
- Rejects and waste material: It is one of the best indicators of craft work. For instance, if shell or stone is cut to make objects, then pieces of these materials will be discarded as waste at the place of production.
- Finished products: Sometimes, larger waste pieces were used up to make smaller objects which suggest that apart from small, specialised centres, craft production was also undertaken in large cities such as Mohenjodaro and Harappa.