The Geographical Survey of India (GSI) provided estimates for the amount of gold that can be extracted from a site in Sonbhadra district of Uttar Pradesh.
The total gold that can be extracted is found to be 160 kg.
GSI arrived at this estimate by two basic processes,
by the study of rocks, and drilling of the ground. Laboratory analysis of the rocks indicates the possibility of these containing a particular mineral. And,
another indicator is the age of the rocks, which is determined by radiometric dating processes.