@misc{indiciae3bffdbf98718,
  title = {Gemstones: An overview of production of specific U.S. gemstones},
  author = {Gordon T. Austin},
  year = {1995},
  doi = {10.3133/7000012},
  url = {https://pubs.usgs.gov/publication/7000012},
  note = {Source identifier: 7000012}
}