Opal from selected localities.
Spain | |
| Mineralogistes de Catalunya (1997), VII (1): 34-55 |
| Laura Palacios Pérez, Minerals i roques, Pòrtic Natura, 2003 |
Spain | |
| Mineralogistes de Catalunya (1997), VII (1): 34-55 |
| Laura Palacios Pérez, Minerals i roques, Pòrtic Natura, 2003 |