- Cripple Creek Mining District
| Betts, John (n.d.) John Betts website listing. Foord, Eugene E., Taggart, Joseph E. (1998) A reexamination of the turquoise group: the mineral aheylite, planerite (redefined), turquoise and coeruleolactite. Mineralogical Magazine, 62 (1) 93-111 doi:10.1180/002646198547495 |
General Trimble's Mine, East Whiteland Township, Chester County, Pennsylvania, USA