Wyoming State Geological Survey,
Hausel, W. Dan.
Sutherland, Wayne M.
Wyoming State Geological Survey.
Preliminary report on gemstones, semi-precious stones, lapidary materials, ornamental stones, and other unique minerals and rocks of Wyoming : a field guide for collectors
Preliminary report on gemstones, semi-precious stones, lapidary materials, ornamental stones, and other unique minerals and rocks of Wyoming : a field guide for collectors
Preliminary report on gemstones, semi-precious stones, lapidary materials, ornamental stones, and other unique minerals and rocks of Wyoming :