Longleaf Mineral Co. Call or text(936) 289-3438

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San Augustine County, Texas

Sell Mineral Rights in San Augustine County, Texas

The deepest, hottest part of the Shelby Trough. Rockcliff bought Pine Wave's East Texas platform here in October 2025, and Aethon, Adamas and EXCO have all filed this year.

Producing formations: Haynesville, Bossier

Call or text (936) 289-3438

What is under San Augustine County
Surface Shallow section Travis Peak / Hosston Cotton Valley Bossier Haynesville ~8,000 ft ~10,000 ft ~12,500 ft ~14,500 ft ~17,500 ft Gas, older vertical wells Gas, the legacy East Texas pay Gas, drilled with the Haynesville The deep, overpressured target

Depths are approximate and vary across the county. The Haynesville in San Augustine sits among the deepest and hottest anywhere in the play, which is why it took high-pressure completion design to make it work, and why older deeds here often severed only the shallow rights.


Who is operating in San Augustine County

These operators have filed permits or completions in San Augustine County with the Railroad Commission in 2026. If your check comes from one of them, we already know the wells.

  • Rockcliff Energy Operating III
  • Aethon Energy Operating
  • Adamas Energy
  • EXCO Operating
  • Apex Natural Gas
  • BPX Operating

What we buy in San Augustine County

Mineral rights, royalty interests, overriding royalty, non-participating royalty, non-operated working interest, and non-producing minerals. There is no size limit in either direction. We buy a single interest in one unit and we buy whole family positions.

If your piece feels too small to bother with, call anyway. Small interests in the same tract usually belong to relatives, and we would rather work with the whole family at once.

How an offer gets made

You call or fill out the form. We pull the county records, the appraisal district roll and the Railroad Commission production history ourselves. Within three business days you get a specific cash number in writing and a plain explanation of how we got there. If we think you should hold, we say that too. We cover title, recording and closing, and you keep every royalty check until the day we close.

Call or text (936) 289-3438 Or email offers@longleafmineralco.com


Why we work this county

We buy the San Augustine County mineral appraisal roll every year and read it. Three things about this county keep us here.

Most owners do not live here. Of the individuals on the roll, roughly four out of five have a mailing address somewhere other than San Augustine County. A good number are in Houston, Dallas and Tyler, and a surprising number are in California and Louisiana. Almost all of them inherited the interest and have never seen the ground.

Most interests are small, and most of them should not be. The typical owner here holds a fraction of a fraction, because a tract got split among children, then grandchildren, and nobody ever put it back together. An interest that looks too small to bother with is usually one piece of something considerably larger.

The rock is real. This is the deep end of the Shelby Trough, and the operators working it are not small companies. That is why an offer here has to be built on what the wells will actually do rather than on a rule of thumb.


Who holds the value, by operator

Straight off the 2026 roll, by total appraised value of the interests under each operator.

OperatorAppraised value on the roll
Adamas Energy$565.4 million
Rockcliff Energy Operating III$108.0 million
XTO Energy$88.8 million
BPX Operating$50.5 million
Rockcliff Energy Operating$15.5 million
Silver Hill Energy Operating$6.6 million
EXCO Operating$6.6 million
Merit Energy$3.1 million
Apex Natural Gas$2.9 million

Rockcliff bought Pine Wave Energy Partners' East Texas platform in October 2025, roughly 29,000 net acres and 25 operated wells across San Augustine and Shelby. If your division order changed names recently, that is usually why.