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Austria | |
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| R. Exel: Die Mineralien und Erzlagerstätten Österreichs (1993) |
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Cuba | Mineral Collector 10:118 (1903) |
| Mineral Collector 10:118 (1903) |
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Slovakia | |
|
| Koděra, M. et al., 1986 a 1990 : Topografická mineralógia Slovenska, diel 1- 3, Veda – Vydavateľstvo SAV, Bratislava, 1990, 1 – 1590 |
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USA | |
|
| Minerals of Colorado (1997) E.B. Eckels |
|
| Jay Ellis Ransom,1974, Gems and Minerals of America |
|
| Ransom, 1974. Gems and Minerals of America |
|
| Ransom, 1974. Gems and Minerals of America |
|
| Jay Ellis Ransom,1974,Gems and Minerals of America |
|
| MacFall (1975) Gem Hunter's Guide |
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| |
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| Extra Lapis - English No. 10 Opal |