Mineral Rights not owned.
The mineral reservation, if valid, will appear of the face of the deed and will either be specific as to coal or general as to all oil, gas and mineral rights. The more specific reservations would apply to coal only and would free up your other mineral interests. The more general reservation would apply to coal as well as oil, gas and other minerals. I am not familiar with specific laws in your state. Many have obligations in order to preserve/maintain reserved or severed minerals, including obligations to be of record claiming same every 20 years or so. Again, check for specifics in your state.