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:
Portland, Cumberland Co., Maine, USA

Oldest recorded age at locality: 265
Youngest recorded age at locality: 263

mindat Locality ID: 52939
mindat URL: http://www.mindat.org/loc-52939.html

Tectonic Settings:

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

Number of Child Localities: 4
Child Localities:
Great Diamond Island
Jewell Island
Municipal Quarry
Peaks Island

Latitude: 0°0'0"N
Longitude: 0°0'0"E
Decimal Degree (lat, lon): 0,0

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.

Arsenopyrite	Clay	Clinozoisite	Epidote	Feldspar	Garnet	Mica	None	Pyrite	Quartz
Tourmaline

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 As B Ca Fe H K Na O S Si

Elements from minerals reported directly at this locality: Al Fe H K O Si

Structural Groups for minerals in this locality:
Arsenopyrite Clay Clinozoisite Epidote Feldspar Garnet Mica None Pyrite Quartz
Tourmaline

9 IMA Minerals at location:

Albite ()*	Almandine ()*	Annite ()*	Arsenopyrite ()*	Epidote ()*
Microcline ()*	Pyrite ()*	Quartz ()*	Schorl ()*

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
Albite ()*	Feldspar	Na(AlSi₃O₈)	265	263	1	216864	8803
Almandine ()*	Garnet	Fe²⁺₃Al₂(SiO₄)₃	265	263	0		2353
Annite ()*	Mica Clay	KFe²⁺₃(AlSi₃O₁₀)(OH)₂	265	263	0		356
Arsenopyrite ()*	Arsenopyrite	FeAsS	265	263	1	216864	9052
Epidote ()*	Epidote Clinozoisite	Ca₂(Al₂Fe³⁺)[Si₂O₇][SiO₄]O(OH)	265	263	1	216864	8173
Microcline ()*	Feldspar	K(AlSi₃O₈)	265	263	1	216864	4924
Pyrite ()*	Pyrite	FeS₂	265	263	1	216864	39462
Quartz ()*	Quartz	SiO₂	265	263	2	216862,216864	61156
Schorl ()*	Tourmaline	NaFe²⁺₃Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)	265	263	1	216864	2705

1 Ages assigned to this locality:

	Excel ID	Max Age (Ma)	Min Age (Ma)	Age as listed in reference	Dating Method	Age Interpret	Prioritized?	Sample Source	Sample Num	Run Num	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 DOI	Reference ID	Age Notes
	Bradley_2012_092	265	263	264±1	U/Pb			zircon			Yes	Zircon			237377	Sebago, Cumberland Co., Maine, USA	Mt. Mica (Irish Pit)	McCauley and Bradley (2014)	10.3749/canmin.52.2.183	CM52_183

Sample	Source Locality	Reference URL

All locality data graciously provided by mindat.org

All age data...