Old petrified stump
Looks like a pine tree lighter-wood stump. It the wood should be pine resin soaked.
When cut and split into pencil size pieces, it is excellent fire starter.
It has value cut and split into firestarter. My guess is one stump would be good for personal use for the rest of your like.
In bulk, where you have acres of land with quite a few stumps per acre, The stumps can be harvested after a clearcut of the existing trees.
The only company I know of that may still purchase stumps in SC is Hercules, Inc.
This is a similar company in Georgia that shows info on the process of harvest:
I do not know who would buy in Chesterfield County, SC. My suggestion is to contact the SC Forestry Service.