OF-00-11 Evaluation of Mineral and Mineral Fuel Potential of Saguache County State Mineral Lands Administered by the Colorado State Land Board


This report for Saguache County includes an introduction to the geology and mineral resources of the county along with an index map of tract locations, maps of metallic mineral prospects, industrial mineral prospects and oil and gas test wells and oil field locations. The main body of the report is an evaluation of each individual tract, which includes text as well as a topographic map and a geologic map. Digital PDF download. Digital ZIP download. OF-00-11D

Four general categories of resources are included in this inventory:

  • oil and gas
  • coal
  • metallic minerals
  • industrial minerals and construction materials

Each individual tract evaluation includes:

  • A bar graph which ranks each tract’s resource potential for each of the four mineral categories. An explanation of the categories may be found at the end of this introduction
  • Tract identifier number, county name, and county location map
  • Tract location on a 7-1/2-minute United States Geologic Survey topographic map
  • Tract location on a United States Geologic Survey surface outcrop map
  • Location as to section, township, and range and approximate acreage
  • Overview of tract geology
  • Specific assessment of the resource potential for the four resource categories
  • References used in assessing tract potential

Saguache County is a large, sparsely populated county in southwestern Colorado, and most of the population of the county resides in the San Luis Valley. The valley is located within the southeastern one-third portion of the county. This evaluation of the mineral and mineral fuel resource potential was conducted for the nearly 130,000 acres of state mineral lands within the county. It was conducted as part of its long-term evaluation of approximately 4 million acres of state lands administered by the State Land Board. For evaluation purposes, the county was divided into 85 individual tracts that range from approximately 40 acres to 33,000 acres.

Mineral production in the county has been of moderate. Metal mining has been the most significant production, with silver, gold, lead, zinc, iron, and uranium being the most important metals. Currently, no metal mining is being done in the county, although resources do exist. Little, if any oil and gas has been produced in the county. No coal resources are known to exist. The Hall Mine west of Villa Grove was at one time a large supplier of turquoise. The county has potentially large resources of perlite, a lightweight aggregate, in the volcanic rocks of the northeastern San Juan Mountains. Very large resources of gravel and sand exist in and around the San Luis Valley. The county has never been a large producer of industrial minerals of any type.