@misc{indiciae53f20dad4110,
  title = {Reported occurrences of selected minerals in Colorado: Includes most metals and nonmetals; does not include mineral fuels, sodium and potassium salts, or phosphate},
  author = {Conservation Division Branch of Mineral Classification},
  year = {1971},
  doi = {10.3133/mr57},
  url = {https://pubs.usgs.gov/publication/mr57},
  note = {Source identifier: mr57}
}