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Přírodní uran Special Interest on TARIC code 2844 10 10 for European Natural Uranim : Uranium Přírodní uran Prírodný urán Urânio natural Uranio Naturlig uran natürliches Uran Ουράνιο φυσικό Natural uranium Uranium naturel Uranio naturale natuurlijk uranium luonnonuraani Naturligt uran Looduslik uraan dabiskais urāns Gamtinis uranas: Természetes urán: Naturalny uran naravni uran:

Uranium mineral resources of the Czech Republic

Exploitable ~~/utilizable~~ accumulations of uranium have been found both in the crytalline basement and in cover formations of the Bohemian Massif. The uranium ores originated in two major phases – Late Variscan and Alpine. The deposits can be divided into six morphogenetic types:

Graphitized crashed zones in crystalline rocks with a veinlet-disseminated type. Major ore minerals are uraninite, coffinite and brannerite (e.g. Rožná, Olší, Zadní Chodov, Dyleň, Okrouhlá Radouň deposits)

Veins and vein systems – hydrothermal deposits, with a predominance of carbonate-uraninite mineralization, spatially and genetically associated with massifs of Variscan granitoids (formerly important deposits of the Jáchymov, Horní Slavkov and Příbram districts, small deposits in the area of the Železné hory Mts. (Licoměřice-Březinka, Bernardov), Krkonoše Mts. (e.g.. Bedřichov), Rychleby Mts. (Zálesí u Javorníka) e.o.

A metasomatic mineralization combined with chloritized tectonic zones in Variscan granitoids with mainly uraninite-coffinite-brannerite mineralization (Vítkov 2, Lhota u Tachova, Nahošín).

A stratiform mineralization in sediments of the Upper Palaeozoic, formed by uranium-bearing coal seams and host rocks in the Upper Carboniferous and Lower Permian of the Intrasudetic (e.g. Radvanice, Bečkov) and Kladno-Rakovník Basins (Rynholec).

Mainly stratiform mineralization in the Cretaceous sediments – ore bodies, formed mainly by uraninite and U-blacks, in places also zircon, combined with the Cenomanian sediments of the Lužice development of the Bohemian Cretaceous Basin in Stráž pod Ralskem surroundings, where both classical underground mining (Hamr, Křižany, Břevniště) and leaching of the ore from boreholes (Stráž) took place.

A stratiform mineralization in Tertiary Basins – minor deposits of rich ores in sediments enriched in organic material in wider surroundings of Karlovy Vary (e.g. Hájek, Hroznětín, Odeř, Ruprechtov).

Deposits of the economical importance, which were intensively exploited especially in the past, are concentrated in five areas. In the following list, these areas with specified type of a mineralization and the most important deposits are arranged according to their importance, given by the amount of the extracted uranium metal. A period during which the exploitation took place is added in parentheses. A proportion of the area on the bulk uranium mining production in the Czech Republic in per cent is given in the end.

Central Bohemian Area – metasomatic and vein mineralization - Příbram (exploited in 1948 – 1990) – about 42 % of the bulk U metal mining production

North Bohemian Area – mineralization in the Cretaceous sediments – Hamr (exploited until 1995), Stráž pod Ralskem (exploited until 1996) – in total about 22 % of the bulk U metal mining production

Moravian Area – disseminated zonal and vein mineralization – Rožná (supposed termination of the exploitaion in 2005), Olší - in total about 17 % of the bulk U metal mining production

West Bohemian Area – metasomatic and disseminated zonal mineralization – Vítkov 2 (exploitation until 1989), Zadní Chodov (exploited in 1954 - 1992) – about 10 % of the bulk U metal production

Krušné hory Mts. Area – mineralization in the Tertiary sediments and vein deposits - Jáchymov (exploited in 1945 – 1964), Horní Slavkov (1948 – 1962) – in total about 9 % of the bulk U metal production

Of the registered deposits , only Rožná deposit was mined in 2003. The uranium has been also extracted within a closing down work at the Stráž pod Ralskem deposit. Underground mining takes place at Rožná (on average grading 0.308 % U in proven reserves), whereas the Stráž deposit (on average grading 0.031 % U in proven reserves) has been exploited by means of in situ leaching (a close of the operation since April 1, 1996). All extracted ore has been chemically processed to provide chemical concentrate (yellow cake). DIAMO, s.p., Stráž pod Ralskem has been the only uranium mini ng company in the Czech Republic and České energetické závody, a. s. has been the exclusive customer to buy U-concentrates.

A tailing pond in Stráž pod Ralskem, where a waste leach of the deposit with 0.030 – 0.063% of rare earths was accumulated for 30 years, is a potential source not only of rare earths (lanthanum – gadolinium) but also scandium, yttrium, niobium, zirconium and hafnium. Except Zr, reserves have not been evaluated yet. The annual uranium consumption (in the nuclear power stations Dukovany and Temelín) reaches 690 – 700 t per year at present. The surplus of the production has been deposited as state material reserves.

Registered deposits in the Czech Republic

1 Hamr 5 Rožná

2 Stráž 6 Brzkov

3 Břevniště 7 Jasenice-Pucov

4 Osečná-Kotel

Basic statistical data of the Czech Republic as of December 31

Year	1999	2000	2001	2002	2003
Registered deposits – total number	13	7	7	7	7
Exploited	1	1	1	1	1
Total mineral resources, t U metal	139 141	137 205	136 943	136 785	136 409
economic proved reserves	20 926	20 389	20 226	1 945	1 710
economic probable reserves	21 720	20 858	20 626	19 448	19 448
potentially economic resources	96 495	95 958	96 091	115 392	115 251
Mining production, t U metal	605	498	490	477	458

Right now we are trying to contact local authorities and experts at:

1 Hamr 5 Rožná

2 Stráž 6 Brzkov

3 Břevniště 7 Jasenice-Pucov

4 Osečná-Kotel

More information at http://www.cita.es/mcr

Ing. Miguel Ángel Gallardo Ortiz, Mining Engineer, E-mail: miguel@cita.es
Apartado (P.O. Box) 17083, E-28080 Madrid, Spain
Tel +34 914743809 Fax 914738197 GSM 619776475