The Mineral Evolution database is currently under development.
The goal of this page is to present localities at which the mineral is found, and estimates of the oldest possible geologic age of the minerals at these localities.
This mineral is using an age reported as an element mineralization period.
O
This mineral is using an age calculated from all data at the locality.
R
The age displayed for this mineral originates from a different, non-child locality.
P
The age displayed for this mineral is the range of ages for this mineral at all of this locality's children.
This mineral's age has not yet been recorded.
This Mineral list contains entries from this locality, including sub-localities. Minerals in bold are reported by mindat.org as occurring directly at this locality, and do not occur at any children (sublocalities) of this locality.Elements at this locality, including sub-localities: AgAlAsAuBaBiCCaCdCeClCoCuFFeHHgKMgMnNaNiOPPbSSbSeSiSnSrTeThTiUVWZnZrElements from minerals reported directly at this locality: Structural Groups for minerals in this locality:
The Zadní Chodov uranium deposit was mined from 1952 to 1992 and was ranked among medium-size uranium deposits in the Bohemian Massif. The totalmine production of low-grade uranium ore (0.195 wt.% U) was 4151 t U. The deposit, which is located in the northern tectonic block of the Bor pluton, was investigated by mine workings down to levels of 1250m in a length of over 2.5 km. The contact with the Moldanubian high-grade metasediments is tectonic, comprising several parallel shear structures to the Zadní Chodov fault,which forms the western boundary of the Bor pluton. Migmatised biotite paragneisses of the Moldanubian Varied Group predominate and they contain intercalations of quartzites, amphibolites, calc-silicate rocks and crystalline limestones. Dykes and bodies of amphibole-biotite tonalites and biotite granites cut the paragneisses. Aplite, pegmatite and lamprophyre dykes occur but are less frequent and are particularly developed above and below large shear zones. Uranium mineralisation is associated with the N-S trending zones of the Zadní Chodov fault in areas of their intersection with NW-SE trending fault structures, which form a NW continuation of the Central fault. The Zadní Chodov shear zone has been verified in an extent exceeding 20 km, its thickness in the middle part reaches 500m, and the dip is 50–75° to the east. This dislocation passes northwards into the Eastern shear zone of the Zadní Chodov deposit. The infill of the shear zones consists of intensely altered and crushed rocks with chlorite-rich and/or clay-mineral-rich assemblages. Uranium mineralisation was concentrated into three shear zones
Giersdorf_00000830
The Vítkov II uranium deposit was mined from 1961 to 1988 and was ranked among medium-size uranium deposits in the Bohemian Massif. The total mine production of low-grade uranium ore (0.124wt.% U)was 3973 t U. This uranium deposit occurs in the central tectonic block of the Bor pluton. The deposit is evolved between two shear NNE–SSW zones. The shear zone 0–30 in the east is up to 5–7 m in thickness. Its infill consists of highly crushed altered rocks (albitised biotite granites and lamprophyres), quartz and carbonates. Rich accumulations of U-minerals often occur in its vicinity. The Vítkov shear zone (southern part of the Eastern shear zone evolved in area of the Zadní Chodov deposit) forms the western boundary of the deposit. It is very conspicuous and its thickness reaches several tens of meters. It is infilled by crushed and altered country rocks. The pennate NW–SE dislocations situated between the two shear zones are infilled by dyke biotite and two-mica granites and relatively rarely aplites. The occurrence of uranium mineralisation is controlled by NW-SE and NNW-SSE trending faults,which forma dense network of fractures and joints. The surrounding biotite granites are usually intensely altered. The ore bodies comprise U-minerals (coffinite, uraninite, brannerite) finely disseminated in the surrounding altered granitoids.
Giersdorf_00000831
The small uranium deposit Lhota is situated in the central block of the Bor pluton. The deposit has been verified between 1953 and 1967 and 1975–1989 by five exploration shafts down to a depth of 250 m, and by numerous boreholes down to levels of 300 to 600m.During these two exploration stages low-grade uranium mineralisation (0.120 wt.% U) with the total amount of 158 t U was identified. The geology of the area surrounding this uranium deposit consists of mostly coarse-grained biotite granites together with smaller bodies of amphibole-biotite granodiorites and tonalites overlain by remnants of the Moldanubian country rocks. Patches of high-grade metamorphic rocks of the Moldanubian Varied group also form abundant xenoliths in the biotite granites. The rock complex is pierced by NW-SE, partly also N-S trending aplite dykes. The two ore bearing shear structures (Os-2, Os-17) strike NW-SE and dip steeply NE. The thickness of these mineralised shear zones is 5–18 m. The mineralised shear zones comprise coffinite, uraninite and brannerite.