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:
Blackburn Circle Locality, Gloucester, Essex Co., Massachusetts, USA

Oldest recorded age at locality: 364.15
Youngest recorded age at locality: 350.45

mindat Locality ID: 206529
mindat URL: http://www.mindat.org/loc-206529.html

Tectonic Settings:

Total number of sublocalities beneath "Blackburn Circle Locality, Gloucester, Essex Co., Massachusetts, USA": 0
Total number of bottom-level sublocalities: 0

Latitude: 42°37'32"N
Longitude: 70°39'45"W
Decimal Degree (lat, lon): 42.625555555556,-70.6625

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.

Amorphous	Amphibole	Astrophyllite	Calcite	Cancrinite-sodalite	Clay	Corundum	Feldspar	Fluorite	Mica
Molybdenite	None	Pyrite	Pyroxene	Quartz	Rocksalt	Rutile	Sodalite	Sphalerite	Spinel
Sulphur	Zircon

Aegirine ()*	Albite ()*	Annite ()*	Astrophyllite ()*	Danalite ()*
Fluorite ()*	Galena ()*	Grunerite ()*	Hematite ()*	Magnetite ()*
Microcline ()*	Molybdenite ()*	Muscovite ()*	Opal ()*	Pyrite ()*
Quartz ()*	Riebeckite ()*	Rutile ()*	Siderite ()*	Sphalerite ()*
Sulphur ()*	Thorite ()*	Zircon ()*

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 F Fe H K Mo Na O Pb S Si Th Ti Zn Zr

Elements from minerals reported directly at this locality: Al Be C Ca F Fe H K Mo Na O Pb S Si Th Ti Zn Zr

Structural Groups for minerals in this locality:
Amorphous Amphibole Astrophyllite Calcite Cancrinite-sodalite Clay Corundum Feldspar Fluorite Mica
Molybdenite None Pyrite Pyroxene Quartz Rocksalt Rutile Sodalite Sphalerite Spinel
Sulphur Zircon

23 IMA Minerals at location:

Mineral name	Structural Groups	IMA Formula	Max Age (Ma)	Min Age (Ma)	# of localities containing mineral
Aegirine ()*	Pyroxene	NaFe³⁺Si₂O₆	364.15	350.45	1022
Albite ()*	Feldspar	Na(AlSi₃O₈)	364.15	350.45	8803
Annite ()*	Mica Clay	KFe²⁺₃(AlSi₃O₁₀)(OH)₂	364.15	350.45	356
Astrophyllite ()*	Astrophyllite	K₂NaFe²⁺₇Ti₂(Si₄O₁₂)₂O₂(OH)₄F	364.15	350.45	161
Danalite ()*	Cancrinite-sodalite Sodalite	Be₃Fe²⁺₄(SiO₄)₃S	364.15	350.45	58
Fluorite ()*	Fluorite	CaF₂	364.15	350.45	9617
Galena ()*	Rocksalt	PbS	364.15	350.45	24243
Grunerite ()*	Amphibole	Fe²⁺₂Fe²⁺₅Si₈O₂₂(OH)₂	364.15	350.45	223
Hematite ()*	Corundum	Fe₂O₃	364.15	350.45	14640
Magnetite ()*	Spinel	Fe²⁺Fe³⁺₂O₄	364.15	350.45	14899
Microcline ()*	Feldspar	K(AlSi₃O₈)	364.15	350.45	4924
Molybdenite ()*	Molybdenite	MoS₂	364.15	350.45	5800
Muscovite ()*	Mica Clay	KAl₂(Si₃Al)O₁₀(OH)₂	364.15	350.45	17380
Opal ()*	Amorphous	SiO₂·nH₂O	364.15	350.45	2994
Pyrite ()*	Pyrite	FeS₂	364.15	350.45	39462
Quartz ()*	Quartz	SiO₂	364.15	350.45	61156
Riebeckite ()*	Amphibole	Na₂(Fe²⁺₃Fe³⁺₂)Si₈O₂₂(OH)₂	364.15	350.45	375
Rutile ()*	Rutile	TiO₂	364.15	350.45	5614
Siderite ()*	Calcite	Fe(CO₃)	364.15	350.45	6417
Sphalerite ()*	Sphalerite	ZnS	364.15	350.45	21482
Sulphur ()*	Sulphur	S	364.15	350.45	2045
Thorite ()*	Zircon	Th(SiO₄)	364.15	350.45	1006
Zircon ()*	Zircon	Zr(SiO₄)	364.15	350.45	5251

2 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
	USGS-Rb-Sr-01308	350.45	350.45	350.45	Rb-Sr	initial age disturbed by weathering		whole rock							206529	Blackburn Circle Locality, Gloucester, Essex Co., Massachusetts, USA		USGS-Rb-Sr		USGS-Rb-Sr
	USGS-Rb-Sr-01309	364.15	364.15	364.15	Rb-Sr	initial age disturbed by weathering		whole rock							206529	Blackburn Circle Locality, Gloucester, Essex Co., Massachusetts, USA		USGS-Rb-Sr		USGS-Rb-Sr

Sample	Source Locality	Reference URL

All locality data graciously provided by mindat.org

All age data...