Known only from drill core samples. Discovered in 1978 as an electromagnetic anomaly. Drilled extensively in 1979-1981. Contains an estimate 1 million short tons of copper and gold bearing sulfides. Appears to be associated with felsic metavolcanic center along the flanks of a metamorphosed mafic complex. Formed within a highly deformed island arc sequence caught up in the continent-continent collision of the Penokean Orogeny.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

12 valid minerals.

Detailed Mineral List:

ⓘ Actinolite

Formula: ◻Ca₂(Mg_4.5-2.5Fe_0.5-2.5)Si₈O₂₂(OH)₂

References:

DeMatties, Theodore A. (1990) The Ritchie Creek main zone: A lower Proterozoic copper-gold volcanogenic massive sulfide deposit in northern Wisconsin. Economic Geology, 85 (8). 1908-1916 doi:10.2113/gsecongeo.85.8.1908

ⓘ Altaite

Formula: PbTe

References:

ⓘ 'Biotite'

Formula: K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂

References:

ⓘ Bornite

Formula: Cu₅FeS₄

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Chalcocite

Formula: Cu₂S

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Chalcopyrite

Formula: CuFeS₂

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ 'Chlorite Group'

References:

ⓘ 'Garnet Group'

Formula: X₃Z₂(SiO₄)₃

References:

ⓘ Magnetite

Formula: Fe²⁺Fe³⁺₂O₄

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Muscovite

Formula: KAl₂(AlSi₃O₁₀)(OH)₂

References:

ⓘ Muscovite var. Sericite

Formula: KAl₂(AlSi₃O₁₀)(OH)₂

References:

ⓘ Native Gold

Formula: Au

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Native Gold var. Electrum

Formula: (Au,Ag)

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Pyrite

Formula: FeS₂

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Pyrrhotite

Formula: Fe_1-xS

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Quartz

Formula: SiO₂

References:

ⓘ Sphalerite

Formula: ZnS

References:

ⓘ 'Tennantite Subgroup'

Formula: Cu₆(Cu₄C²⁺₂)As₄S₁₂S

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ 'Tetrahedrite Subgroup'

Formula: Cu₆(Cu₄C²⁺₂)Sb₄S₁₂S

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘ	Native Gold var. Electrum	1.AA.05	(Au,Ag)
ⓘ		1.AA.05	Au
Group 2 - Sulphides and Sulfosalts
ⓘ	Chalcocite	2.BA.05	Cu₂S
ⓘ	Bornite	2.BA.15	Cu₅FeS₄
ⓘ	Sphalerite	2.CB.05a	ZnS
ⓘ	Chalcopyrite	2.CB.10a	CuFeS₂
ⓘ	Pyrrhotite	2.CC.10	Fe_1-xS
ⓘ	Altaite	2.CD.10	PbTe
ⓘ	Pyrite	2.EB.05a	FeS₂
ⓘ	'Tennantite Subgroup'	2.GB.05	Cu₆(Cu₄C²⁺₂)As₄S₁₂S
ⓘ	'Tetrahedrite Subgroup'	2.GB.05	Cu₆(Cu₄C²⁺₂)Sb₄S₁₂S
Group 4 - Oxides and Hydroxides
ⓘ	Magnetite	4.BB.05	Fe²⁺Fe³⁺₂O₄
ⓘ	Quartz	4.DA.05	SiO₂
Group 9 - Silicates
ⓘ	Actinolite	9.DE.10	◻Ca₂(Mg_4.5-2.5Fe_0.5-2.5)Si₈O₂₂(OH)₂
ⓘ	Muscovite	9.EC.15	KAl₂(AlSi₃O₁₀)(OH)₂
ⓘ	var. Sericite	9.EC.15	KAl₂(AlSi₃O₁₀)(OH)₂
Unclassified
ⓘ	'Biotite'	-	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
ⓘ	'Chlorite Group'	-
ⓘ	'Garnet Group'	-	X₃Z₂(SiO₄)₃

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Actinolite	◻Ca₂(Mg_4.5-2.5Fe_0.5-2.5)Si₈O₂₂(OH)₂
H	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
H	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
H	ⓘ Muscovite var. Sericite	KAl₂(AlSi₃O₁₀)(OH)₂
O	Oxygen
O	ⓘ Actinolite	◻Ca₂(Mg_4.5-2.5Fe_0.5-2.5)Si₈O₂₂(OH)₂
O	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
O	ⓘ Magnetite	Fe²⁺Fe₂³⁺O₄
O	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
O	ⓘ Quartz	SiO₂
O	ⓘ Muscovite var. Sericite	KAl₂(AlSi₃O₁₀)(OH)₂
O	ⓘ Garnet Group	X₃Z₂(SiO₄)₃
F	Fluorine
F	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Mg	Magnesium
Mg	ⓘ Actinolite	◻Ca₂(Mg_4.5-2.5Fe_0.5-2.5)Si₈O₂₂(OH)₂
Mg	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Al	Aluminium
Al	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Al	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
Al	ⓘ Muscovite var. Sericite	KAl₂(AlSi₃O₁₀)(OH)₂
Si	Silicon
Si	ⓘ Actinolite	◻Ca₂(Mg_4.5-2.5Fe_0.5-2.5)Si₈O₂₂(OH)₂
Si	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Si	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
Si	ⓘ Quartz	SiO₂
Si	ⓘ Muscovite var. Sericite	KAl₂(AlSi₃O₁₀)(OH)₂
Si	ⓘ Garnet Group	X₃Z₂(SiO₄)₃
S	Sulfur
S	ⓘ Bornite	Cu₅FeS₄
S	ⓘ Chalcopyrite	CuFeS₂
S	ⓘ Chalcocite	Cu₂S
S	ⓘ Pyrite	FeS₂
S	ⓘ Pyrrhotite	Fe_1-xS
S	ⓘ Sphalerite	ZnS
S	ⓘ Tennantite Subgroup	Cu₆(Cu₄C₂²⁺)As₄S₁₂S
S	ⓘ Tetrahedrite Subgroup	Cu₆(Cu₄C₂²⁺)Sb₄S₁₂S
K	Potassium
K	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
K	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
K	ⓘ Muscovite var. Sericite	KAl₂(AlSi₃O₁₀)(OH)₂
Ca	Calcium
Ca	ⓘ Actinolite	◻Ca₂(Mg_4.5-2.5Fe_0.5-2.5)Si₈O₂₂(OH)₂
Ti	Titanium
Ti	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Fe	Iron
Fe	ⓘ Actinolite	◻Ca₂(Mg_4.5-2.5Fe_0.5-2.5)Si₈O₂₂(OH)₂
Fe	ⓘ Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Fe	ⓘ Bornite	Cu₅FeS₄
Fe	ⓘ Chalcopyrite	CuFeS₂
Fe	ⓘ Magnetite	Fe²⁺Fe₂³⁺O₄
Fe	ⓘ Pyrite	FeS₂
Fe	ⓘ Pyrrhotite	Fe_1-xS
Cu	Copper
Cu	ⓘ Bornite	Cu₅FeS₄
Cu	ⓘ Chalcopyrite	CuFeS₂
Cu	ⓘ Chalcocite	Cu₂S
Cu	ⓘ Tennantite Subgroup	Cu₆(Cu₄C₂²⁺)As₄S₁₂S
Cu	ⓘ Tetrahedrite Subgroup	Cu₆(Cu₄C₂²⁺)Sb₄S₁₂S
Zn	Zinc
Zn	ⓘ Sphalerite	ZnS
As	Arsenic
As	ⓘ Tennantite Subgroup	Cu₆(Cu₄C₂²⁺)As₄S₁₂S
Ag	Silver
Ag	ⓘ Native Gold var. Electrum	(Au,Ag)
Sb	Antimony
Sb	ⓘ Tetrahedrite Subgroup	Cu₆(Cu₄C₂²⁺)Sb₄S₁₂S
Te	Tellurium
Te	ⓘ Altaite	PbTe
Au	Gold
Au	ⓘ Native Gold var. Electrum	(Au,Ag)
Au	ⓘ Native Gold	Au
Pb	Lead
Pb	ⓘ Altaite	PbTe

Other Regions, Features and Areas containing this locality

North AmericaContinent

North America PlateTectonic Plate

Minnesota River DomainDomain
Superior Craton
- Penokean OrogenCraton

USA

Wisconsin
- Ladysmith-Rhinelander Metavolcanic ComplexComplex

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

LaBerge, G.L. Editor (1996) Volcanogenic massive sulfide deposits of northern Wisconsin: A commemorative volume: Institute on Lake Superior Geology Proceedings, 42nd annual meeting: 42 (2), 170 p.

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