I buy minerals or mineral rights all over the USA and sometimes sell some of what I purchase. I sold some last year that had not been drilled on (no activity) in 40 years. They drilled a well last year, it was a dry hole. I laughed all the way to the bank at the others who thought never sell. It can go either way so if you are considering selling check around with other buyers like put on mineralhub.com and maybe only sell half. I sold half of a 200 acre tract in Weld County Colorado that had never been drilled on, but it was permitted for a horizontal Niobrara well, they drilled a dry hole. Needless to say the minerals are not worth near as much now as they were. There is never a sure thing, hardly. You may have received an offer because of permitting in the area or other activity. Use your head and do research and then follow your heart not what I or others here have suggested.