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



Only display mineral occurrences with a max age below:  and a max age above:    
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  • This page displays localities at which this mineral is found, and estimates of the oldest possible geologic age of the mineral at these localities.


    • Minerals queried: Johnwalkite

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    Max Age (Ma)Min Age (Ma)mindat IDLocality containing MineralCountryTectonic SettingsDated Locality IDDated Locality (Max Age)Reference (Max Age)Reference (Min Age)Excel ID (Max Age)Excel ID (Min Age)Query Minerals# of Query Minerals at LocalityLat DegLat MinLat SecLon DegLon MinLon SecDecimal Degree
    3366USAUSAJohnwalkite 1374912-83-42-4937.82,-83.713611111111
    4104South Dakota, USAUSAJohnwalkite 143582-100-5-3243.967222222222,-100.09222222222
    17377Pennington Co., South Dakota, USAUSAJohnwalkite 1435636-103-19-3343.943333333333,-103.32583333333
    4113Keystone District, Pennington Co., South Dakota, USAUSAJohnwalkite 1435255-103-24-843.881944444444,-103.40222222222
    23065Keystone, Keystone District, Pennington Co., South Dakota, USAUSAJohnwalkite 143537-103-25-1443.885277777778,-103.42055555556
    MD20062Champion Mine, Keystone, Keystone District, Pennington Co., South Dakota, USAUSAJohnwalkite 10000000,0

    This mineral directly occurs at 1 locality (1 localities according to mindat, 6 localities if parents are counted as well)
    Of the 1 locality at which this mineral occurs, 0 have an age. (0 of the 6 parent localities have ages)


    MDThe mineral occurs at this locality according to MED, but does not have an age yet.
    MDThe mineral occurs at this locality according to MED, and has an age.
    The mineral occurs at some child of this locality.
    The locality at which the mineral occurs does not have an age...this is the closest parent locality with an age, relative to that mineral. This is not ideal.

    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.

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    If a locality has both a GPS coordinate, and either contains or has at least one child locality containing at least one of the minerals listed above, then this map displays a single marker for that locality.

     This bottom-level locality is directly dated. (0 total)
     This locality is directly dated, but is not bottom-level. (0 total)
     This locality is not directly dated, and is not bottom-level. (0 total)

     This bottom-level locality has an age assigned to it from some other locality. (0 total)
     This locality does not have an age assigned to it. (1 bottom-level + 5 top/mid-level = 6 total)

       






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