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:
Winthrop, Kennebec Co., Maine, USA


mindat Locality ID: 20942
mindat URL: http://www.mindat.org/loc-20942.html

Tectonic Settings:

Total number of sublocalities beneath "Winthrop, Kennebec Co., Maine, USA": 5
Total number of bottom-level sublocalities: 5

Number of Child Localities: 5
Child Localities:
Horseshoe Island Calc-Silicate Locality
Lake Maranacook Staurolite Locality
Towle "Gold" Mine
Winthrop Copperas Mine
Woolworth Farm Occurrence

Latitude: 0°0'0"N
Longitude: 0°0'0"E
Decimal Degree (lat, lon): 0,0
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 Be C Ca Fe H K Mg O S Si 

Elements from minerals reported directly at this locality: 

Structural Groups for minerals in this locality: 
AmphiboleBerylCalciteClayCopiapiteMelanteriteMicaNoneNot in a structural groupPrehnite
PyriteQuartzStaurolite

11 IMA Minerals at location:
Actinolite  (*)Beryl  (*)Calcite  (*)Copiapite  (*)Melanterite  (*)
Muscovite  (*)Prehnite  (*)Pyrite  (*)Quartz  (*)Sillimanite  (*)
Staurolite  (*)
Mineral nameStructural GroupsIMA FormulaMax Age (Ma)Min Age (Ma)# of Sublocalities containing mineralLOCALITY IDs, not mindat ids# of localities containing mineral
Actinolite  (*)Amphibole   Ca2(Mg4.5-2.5Fe2+0.5-2.5)Si8O22(OH)212171213419
Beryl  (*)BerylBe3Al2Si6O1812171254286
Calcite  (*)CalciteCa(CO3)121712127770
Copiapite  (*)CopiapiteFe2+Fe3+4(SO4)6(OH)2·20H2O1217124382
Melanterite  (*)MelanteriteFe(SO4)·7H2O1217124915
Muscovite  (*)Mica ClayKAl2(Si3Al)O10(OH)22217122,21712317380
Prehnite  (*)PrehniteCa2Al(Si3Al)O10(OH)212171231898
Pyrite  (*)PyriteFeS22217123,21712439462
Quartz  (*)QuartzSiO24217121,217122,217123,21712561156
Sillimanite  (*)Not in a structural groupAl2SiO512171211516
Staurolite  (*)StauroliteFe2+2Al9Si4O23(OH)2217122,217123978


No ages have been assigned to this locality yet.
SampleSource LocalityReference URL

All locality data graciously provided by mindat.org

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