Mineral Evolution Database

Created and maintained by the Mineral Evolution Project in partnership with RRUFF and mindat.

Mineral locality data provided by mindat.org

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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:
Little Indian No. 6 Prospect, Marshall Pass District, Saguache Co., Colorado, USA

Oldest recorded age at locality: 203
Youngest recorded age at locality: 94

mindat Locality ID: 118561
mindat URL: http://www.mindat.org/loc-118561.html

Tectonic Settings:

Total number of sublocalities beneath "Little Indian No. 6 Prospect, Marshall Pass District, Saguache Co., Colorado, USA": 0
Total number of bottom-level sublocalities: 0

Latitude: 38°24'19"N
Longitude: 106°19'51"W
Decimal Degree (lat, lon): 38.405277777778,-106.33083333333

A	This mineral is Anthropogenic.
G	This mineral is directly dated.
B	This mineral is reported as having this age.
Y	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.

None

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: Ca H O Si U

Elements from minerals reported directly at this locality: Ca H O Si U

Structural Groups for minerals in this locality:
None

1 IMA Minerals at location:

Uranophane-α ()*

Mineral name	Structural Groups	IMA Formula	Max Age (Ma)	Min Age (Ma)	# of Sublocalities containing mineral	LOCALITY IDs, not mindat ids	# of localities containing mineral
Uranophane-α ()*	None	Ca(UO₂)₂(SiO₃OH)₂·5H₂O	203	94	0		890

Locality Notes from all Ages at Locality:

Age ID	Locality Notes
Giersdorf_00000794	The Lookout claims are a set of 34 claims in Saguache Co., Colorado, in the Marshall Pass uranium district. The district is located about 12 miles southeast of Sargents and spans the Saguache and Gunnison counties. Two of the major ore bodies, including the Lookout 22 body in particular, were found in alluvium at an elevation of approximately 10,000 feet.
Giersdorf_00000795	The Lookout claims are a set of 34 claims in Saguache Co., Colorado, in the Marshall Pass uranium district. The district is located about 12 miles southeast of Sargents and spans the Saguache and Gunnison counties. Two of the major ore bodies, including the Lookout 22 body in particular, were found in alluvium at an elevation of approximately 10,000 feet.
Giersdorf_00000796	The Lookout claims are a set of 34 claims in Saguache Co., Colorado, in the Marshall Pass uranium district. The district is located about 12 miles southeast of Sargents and spans the Saguache and Gunnison counties. Two of the major ore bodies, including the Lookout 22 body in particular, were found in alluvium at an elevation of approximately 10,000 feet.

3 Ages assigned to this locality:

Excel ID	Max Age (Ma)	Min Age (Ma)	Age as listed in reference	Dating Method	Age Interpret	Sample Source	Age from other Locality	Dated Mineral	Minerals explicitely stated as having this age	Age applies to these Elements	MinDat Locality ID	Dated Locality (Max Age)	Location as listed in reference	Reference	Reference ID	Age Notes
Giersdorf_00000794	94	94	94	202Pb-238U	The ages given are noted by the author to be insufficiently sourced as they are only derived from a single sample. The author expresses that more Marshall Pass uranium minerals should be dated to collect an average age for the set of deposits.	uraninite	Yes	Uraninite	Autunite, Boltwoodite, Chalcocite, Chalcopyrite, Covellite, Galena, Ianthinite, Marcasite, Metazeunerite, Pyrite, Schoepite, Soddyite, Sphalerite, Uraninite, Zeunerite	U	30136	Lookout No. 22 Claim, Marshall Pass District, Saguache Co., Colorado, USA	Lookout No. 22 Claim	Gross (1965)	AM50_909	Pb202-U238 age for a uraninite sample
Giersdorf_00000795	99	99	99	207Pb-235U	The ages given are noted by the author to be insufficiently sourced as they are only derived from a single sample. The author expresses that more Marshall Pass uranium minerals should be dated to collect an average age for the set of deposits.	uraninite	Yes	Uraninite	Autunite, Boltwoodite, Chalcocite, Chalcopyrite, Covellite, Galena, Ianthinite, Marcasite, Metazeunerite, Pyrite, Schoepite, Soddyite, Sphalerite, Uraninite, Zeunerite	U	30136	Lookout No. 22 Claim, Marshall Pass District, Saguache Co., Colorado, USA	Lookout No. 22 Claim	Gross (1965)	AM50_909	Pb207-U235 age for a uraninite sample
Giersdorf_00000796	203	203	203	207Pb-206Pb	The ages given are noted by the author to be insufficiently sourced as they are only derived from a single sample. The author expresses that more Marshall Pass uranium minerals should be dated to collect an average age for the set of deposits.	uraninite	Yes	Uraninite	Autunite, Boltwoodite, Chalcocite, Chalcopyrite, Covellite, Galena, Ianthinite, Marcasite, Metazeunerite, Pyrite, Schoepite, Soddyite, Sphalerite, Uraninite, Zeunerite	U	30136	Lookout No. 22 Claim, Marshall Pass District, Saguache Co., Colorado, USA	Lookout No. 22 Claim	Gross (1965)	AM50_909	Pb207-Pb206 age for a uraninite sample

Sample	Source Locality	Reference URL

All locality data graciously provided by mindat.org

All age data...