Opal from selected localities.
UK | |
| Phillips, W. (1823): An Elementary Introduction to the Knowledge of Mineralogy, 3rd ed. William Phillips (London), 535 pp.; Hogg, T. (1825): A Manual of Mineralogy. Polyblank Publishers (London), p. 191; Hall, T.M. (1868): The Mineralogist's Directory. Edward Stanford (London), 168 pp. |
| [var: Isopyre] Paul De Bondt collection |
| Hall, T.M. (1868): The Mineralogist's Directory. Edward Stanford (London), 168 pp.; Collins, J.H. (1892): "A Handbook to the Mineralogy of Cornwall and Devon", 2nd ed., D. Bradford Barton Ltd. (Truro, UK), 108 pp. |
| Robin Selley and Roger Eslick (2004) Cathedral Mine. BMS Newsletter 68:13-14 |
South Wheal Basset, Carnkie, Carn Brea, Cornwall, England, UK