Mineral Evolution Database
Created and maintained by the Mineral Evolution Project in partnership with RRUFF and mindat.
Mineral locality data provided by mindat.org



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.


Locality Name:
Maybell District, Moffat Co., Colorado, USA

Oldest recorded age at locality: 23.03
Youngest recorded age at locality: 5.3

mindat Locality ID: 133365
mindat URL: http://www.mindat.org/loc-133365.html

Tectonic Settings:

Total number of sublocalities beneath "Maybell District, Moffat Co., Colorado, USA": 43
Total number of bottom-level sublocalities: 41

Number of Child Localities: 34
Child Localities:
Agnes No. 7 Claim
Airborne Anomaly 56-15 Occurrence
Bob Cat Group
Buffalo Head Prospect (Buffalo Head Mining Company Claim No. 6)
Butler Lease
Carol J. Claims
Cedars Prospect Claim No. 1
Hex Claims
Hudson Claim Group
Iron And Copper Claims (MRDS - 10215217)
Johnson Lease
Juniper Springs
Lay - Governor Groups
Leon Claims
Lucky Boy Claim
Maybell Mines
Orr Et Al Claims
Rob Rollo Mine
Sage - Buella Mine (Tec G-Pit 1975)
Section 16 T6N R94W
Section 16 T7N R93W
September Morn Claims
Shell Group
Star Prospect
Sugar Loaf Mine
Tec Open Pit A Thru L (Maybell Pit; Robb Pit)
Trevenen Claims
Unknown Uranium Occurrence (MRDS - 10017429)
Unknown Uranium Occurrence (MRDS - 10017436)
Unknown Uranium Occurrence (MRDS - 10017551)
Unknown Uranium Occurrence (MRDS - 10091313)
Unknown Vanadium - Uranium Occurrence (MRDS - 10017433)
Unknown Vanadium - Uranium Occurrence (MRDS - 10017553)
Unknown Vanadium - Uranium Occurrence (MRDS - 10091315)

Latitude: 40°32'5"N
Longitude: 107°58'16"W
Decimal Degree (lat, lon): 40.534722222222,-107.97111111111
AThis mineral is Anthropogenic.
GThis mineral is directly dated.
BThis mineral is reported as having this age.
YThis mineral is using an age reported as an element mineralization period.
OThis mineral is using an age calculated from all data at the locality.
RThe age displayed for this mineral originates from a different, non-child locality.
PThe 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: Al C Ca Cu F Fe H K Mg Mo Na O P S Se Si U V 

Elements from minerals reported directly at this locality: Al C H O P U 

Structural Groups for minerals in this locality: 
AluniteAmorphousApatiteAutuniteCalciteClayFluoriteFritzscheiteGypsumMeta-autunite
MolybdeniteNonePhosphuranylitePyriteQuartzSchoepiteSmectite-vermiculiteSulphurZircon

28 IMA Minerals at location:
Autunite  (*)Becquerelite  (*)Calcite  (*)Carnotite  (*)Coffinite  (*)
Fluorapatite  (*)Gypsum  (*)Ilsemannite  (*)Jarosite  (*)Jordisite  (*)
Liebigite  (*)Meta-autunite  (*)Metatorbernite  (*)Metatyuyamunite  (*)Molybdenite  (*)
Montmorillonite  (*)Opal  (*)Phosphuranylite  (*)Pyrite  (*)Quartz  (*)
Rutherfordine  (*)Sabugalite  (*)Schoepite  (*)Schröckingerite  (*)Selenium  (*)
Tyuyamunite  (*)Uraninite  (*)Uranophane-α  (*)
Mineral nameStructural GroupsIMA FormulaMax Age (Ma)Min Age (Ma)# of Sublocalities containing mineralLOCALITY IDs, not mindat ids# of localities containing mineral
Autunite  (*)AutuniteCa(UO2)2(PO4)2·10-12H2O23.035.32192866,1928671272
Becquerelite  (*)NoneCa(UO2)6O4(OH)6·8H2O23.035.32192866,19286792
Calcite  (*)CalciteCa(CO3)23.035.32192863,19286827770
Carnotite  (*)NoneK2(UO2)2(VO4)2·3H2O23.035.33192866,192867,1928681184
Coffinite  (*)ZirconU(SiO4)·nH2O23.035.35192854,192866,192867,192871,192885566
Fluorapatite  (*)ApatiteCa5(PO4)3F23.035.32192864,1928662740
Gypsum  (*)GypsumCa(SO4)·2H2O23.035.33192863,192868,1928776890
Ilsemannite  (*)NoneMo3O8·nH2O (?)23.035.31192868123
Jarosite  (*)AluniteKFe3+3(SO4)2(OH)623.035.32192863,1928682228
Jordisite  (*)AmorphousMoS223.035.31192868102
Liebigite  (*)NoneCa2(UO2)(CO3)3·11H2O23.035.3119286678
Meta-autunite  (*)Meta-autuniteCa(UO2)2(PO4)2·6H2O23.035.32192866,192867388
Metatorbernite  (*)NoneCu(UO2)2(PO4)2·8H2O23.035.31192866443
Metatyuyamunite  (*)FritzscheiteCa(UO2)2(VO4)2·3H2O23.035.33192863,192866,192867129
Molybdenite  (*)MolybdeniteMoS223.035.311928775800
Montmorillonite  (*)Clay Smectite-vermiculite(Na,Ca)0.3(Al,Mg)2Si4O10(OH)2·nH2O23.035.311928631508
Opal  (*)AmorphousSiO2·nH2O23.035.32192866,1928672994
Phosphuranylite  (*)PhosphuranyliteKCa(H3O)3(UO2)7(PO4)4O4·8H2O23.035.31192867182
Pyrite  (*)PyriteFeS223.035.33192863,192866,19286839462
Quartz  (*)QuartzSiO223.035.32192863,19286861156
Rutherfordine  (*)None(UO2)(CO3)23.035.3058
Sabugalite  (*)NoneHAl(UO2)4(PO4)4·16H2O23.035.3087
Schoepite  (*)Schoepite(UO2)4O(OH)6(H2O)623.035.32192866,19286794
Schröckingerite  (*)NoneNaCa3(UO2)(SO4)(CO3)3F·10H2O23.035.31192866128
Selenium  (*)SulphurSe23.035.31192867143
Tyuyamunite  (*)NoneCa(UO2)2(VO4)2·5-8H2O23.035.32192866,192867628
Uraninite  (*)FluoriteUO223.035.35192854,192866,192867,192870,1928712718
Uranophane-α  (*)NoneCa(UO2)2(SiO3OH)2·5H2O23.035.37192847,192848,192866,192867,192868,192869,192877890


Locality Notes from all Ages at Locality:
Age IDLocality Notes
Giersdorf_00000809Economic ore deposits of the Maybell area are found in the uppermost sandstone unit of the Browns Park Formation. The uranium ore deposits are described as tabular, amoeba-shaped lenses of discontinuous bodies within limited stratigraphic intervals.


1 Ages assigned to this locality:

Excel IDMax Age (Ma)Min Age (Ma)Age as listed in referenceDating MethodAge InterpretPrioritized?Sample SourceSample NumRun NumAge from other LocalityDated MineralMinerals explicitely stated as having this ageAge applies to these ElementsMinDat Locality IDDated Locality (Max Age)Location as listed in referenceReferenceReference DOIReference IDAge Notes
Giersdorf_0000080923.035.323.03-5.3 The Browns Park formation is dated to be Miocene in age and is applied to the uranium mineralization within it.    Autunite, Becquerelite, Carnotite, Coffinite, Liebigite, Schoepite, Torbernite, Tyuyamunite, Uraninite, ZeuneriteU133365Maybell District, Moffat Co., Colorado, USAMaybell Mining DistrictChenoweth (1986) NINCG_289In the Maybell area, the Browns Park formation unconformably overlies truncated rocks ranging In age from Precambrian to Eocene, on the north flank of the Axial Basin anticline. The Browns Park formation is dated to be Miocene in age.

SampleSource LocalityReference URL

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