Chalcedony from
Mexico | |
| Dennis Tryon collection |
USA | |
| Luetcke, Rolf (n.d.) Personal communication. |
| Luetcke, Rolf (n.d.) Personal communication. |
| Luetcke, Rolf (n.d.) Personal communication. |
| Luetcke, Rolf (n.d.) Personal communication. |
| Luetcke, Rolf (n.d.) Personal communication. |
Hardshell Mine, Hardshell Gulch, Harshaw, Harshaw Mining District, Patagonia Mountains, Santa Cruz County, Arizona, USA