I am able to find only few papers related to trace element concentrations in coal and coal dust. Please suggest a few articles regarding the such works.
Not sure if this U.S. Geological Survey website and web map will have the data that you need. I think it does have some trace element data for India. You can download the U.S. Geological Survey coal quality data for India: https://www.usgs.gov/centers/geology%2C-energy-%26amp%3Bamp%3B-minerals-science-center/science/world-coal-quality-inventory-data