Oligoclase from Delaware County, Pennsylvania, USA
USA | |
| Gordon, "Mineralogy of Pennsylvania" 1922 p. 193. |
| Rocks & Min.:59:109-120. |
| Rocks & Min.: 59:109-120 & 62:176-178. |
| Mineralogy of Pennsylvania - 1922 Samuel S. Gordon pgs. 199-200 |
USA | |
| Gordon, "Mineralogy of Pennsylvania" 1922 p. 193. |
| Rocks & Min.:59:109-120. |
| Rocks & Min.: 59:109-120 & 62:176-178. |
| Mineralogy of Pennsylvania - 1922 Samuel S. Gordon pgs. 199-200 |