Hi Cynthia -
Karnes County is one of the most productive Counties in Texas. I have to agree with Marcus T that I would urge you to be very hesitant to sell.
Having said that, depending upon where the subject lands are located Karnes County, your interests could be worth thousands upon thousands upon thousands of dollars per net mineral acre.
If you will post your legal description, I will be happy to take a look at your area and send you some information on what is happening on the ground. If you would prefer to send me the legal description privately, accept my offer to become A Friend on The Forum and send it to me that way.
Hope this helps -
Charles Emery Tooke III
Certified Professional Landman
Fort Worth, Texas