Habit: Thick crusts composed of millions of hair-like mordenite crystals. The crystals are very elongated and can easily reach 2 inches, and have grown subparallel next to each other, perpendicular to the matrix.

Colour: Individual crystals are colorless, but the general appearance of the mineral is white, due to the very many crystals right next to one another.

Description: Thanks to mindat member John Cornish, this locality has yielded many world class specimens of mordenite, and continues to set the standard for the species.

References:

Ream, Lanny R. (2004) Idaho Minerals (2nd ed.) L. R. Ream Publishing.

ⓘ Opal

Formula: SiO₂ · nH₂O

References:

John Cornish collection

ⓘ Opal var. Opal-AN

Formula: SiO₂ · nH₂O

References:

John Cornish collection

ⓘ Quartz

Formula: SiO₂

References:

Fluorescent Zeolites and Associated Minerals from the Rat's Nest Mine, Challis, Idaho: John Cornish, Jan 7, 2005

ⓘ Quartz var. Agate

Formula: SiO₂

References:

Ream, Lanny R. (2004) Idaho Minerals (2nd ed.) L. R. Ream Publishing.

ⓘ Quartz var. Amethyst

Formula: SiO₂

References:

Ream, Lanny R. (2004) Idaho Minerals (2nd ed.) L. R. Ream Publishing.

ⓘ Quartz var. Chalcedony

Formula: SiO₂

References:

Ream, Lanny R. (2004) Idaho Minerals (2nd ed.) L. R. Ream Publishing.

ⓘ Stilbite-Ca

Formula: NaCa₄(Si₂₇Al₉)O₇₂ · 28H₂O

References:

David Eicher

ⓘ 'Stilbite Subgroup'

Formula: M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O

References:

Fluorescent Zeolites and Associated Minerals from the Rat's Nest Mine, Challis, Idaho: John Cornish, Jan 7, 2005

Gallery:

Na(AlSi₂O₆) · H₂Oⓘ Analcime

Analcime

Rat's Nest claim, Custer County, Idaho, USA

Analcime

Rat's Nest claim, Custer County, Idaho, USA

Analcime

Rat's Nest claim, Custer County, Idaho, USA

(Ca,Na)₅(Si₂₇Al₉)O₇₂ · 26H₂Oⓘ Heulandite-Ca

Heulandite-Ca, etc.

Rat's Nest claim, Custer County, Idaho, USA

Heulandite-Ca, etc.

Rat's Nest claim, Custer County, Idaho, USA

Heulandite-Ca, etc.

Rat's Nest claim, Custer County, Idaho, USA

Heulandite-Ca, etc.

Rat's Nest claim, Custer County, Idaho, USA

Heulandite-Ca, etc.

Rat's Nest claim, Custer County, Idaho, USA

Heulandite-Ca, etc.

Rat's Nest claim, Custer County, Idaho, USA

Heulandite-Ca, etc.

Rat's Nest claim, Custer County, Idaho, USA

Heulandite-Ca, etc.

Rat's Nest claim, Custer County, Idaho, USA

(Na₂,Ca,K₂)₄(Al₈Si₄₀)O₉₆ · 28H₂Oⓘ Mordenite

Mordenite, etc.

Rat's Nest claim, Custer County, Idaho, USA

Mordenite, etc.

Rat's Nest claim, Custer County, Idaho, USA

Mordenite

Rat's Nest claim, Custer County, Idaho, USA

Mordenite, etc.

Rat's Nest claim, Custer County, Idaho, USA

Mordenite, etc.

Rat's Nest claim, Custer County, Idaho, USA

Mordenite

Rat's Nest claim, Custer County, Idaho, USA

Mordenite, etc.

Rat's Nest claim, Custer County, Idaho, USA

Mordenite, etc.

Rat's Nest claim, Custer County, Idaho, USA

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘ	Quartz var. Agate	4.DA.05	SiO₂
ⓘ	var. Amethyst	4.DA.05	SiO₂
ⓘ	var. Chalcedony	4.DA.05	SiO₂
ⓘ		4.DA.05	SiO₂
ⓘ	Opal var. Opal-AN	4.DA.10	SiO₂ · nH₂O
ⓘ		4.DA.10	SiO₂ · nH₂O
Group 5 - Nitrates and Carbonates
ⓘ	Calcite	5.AB.05	CaCO₃
Group 9 - Silicates
ⓘ	Augite	9.DA.15	(Ca_xMg_yFe_z)(Mg_y1Fe_z1)Si₂O₆
ⓘ	Analcime	9.GB.05	Na(AlSi₂O₆) · H₂O
ⓘ	Laumontite	9.GB.10	CaAl₂Si₄O₁₂ · 4H₂O
ⓘ	Mordenite	9.GD.35	(Na₂,Ca,K₂)₄(Al₈Si₄₀)O₉₆ · 28H₂O
ⓘ	Heulandite-Ca	9.GE.05	(Ca,Na)₅(Si₂₇Al₉)O₇₂ · 26H₂O
ⓘ	Heulandite-Na ?	9.GE.05	(Na,Ca,K)₆(Si,Al)₃₆O₇₂ · 22H₂O
ⓘ	Stilbite-Ca	9.GE.10	NaCa₄(Si₂₇Al₉)O₇₂ · 28H₂O
Unclassified
ⓘ	'Stilbite Subgroup'	-	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
H	ⓘ Opal var. Opal-AN	SiO₂ · nH₂O
H	ⓘ Laumontite	CaAl₂Si₄O₁₂ · 4H₂O
H	ⓘ Mordenite	(Na₂,Ca,K₂)₄(Al₈Si₄₀)O₉₆ · 28H₂O
H	ⓘ Opal	SiO₂ · nH₂O
H	ⓘ Stilbite Subgroup	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O
H	ⓘ Heulandite-Ca	(Ca,Na)₅(Si₂₇Al₉)O₇₂ · 26H₂O
H	ⓘ Heulandite-Na	(Na,Ca,K)₆(Si,Al)₃₆O₇₂ · 22H₂O
H	ⓘ Stilbite-Ca	NaCa₄(Si₂₇Al₉)O₇₂ · 28H₂O
C	Carbon
C	ⓘ Calcite	CaCO₃
O	Oxygen
O	ⓘ Quartz var. Agate	SiO₂
O	ⓘ Quartz var. Amethyst	SiO₂
O	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
O	ⓘ Augite	(Ca_xMg_yFe_z)(Mg_y1Fe_z1)Si₂O₆
O	ⓘ Calcite	CaCO₃
O	ⓘ Quartz var. Chalcedony	SiO₂
O	ⓘ Opal var. Opal-AN	SiO₂ · nH₂O
O	ⓘ Laumontite	CaAl₂Si₄O₁₂ · 4H₂O
O	ⓘ Mordenite	(Na₂,Ca,K₂)₄(Al₈Si₄₀)O₉₆ · 28H₂O
O	ⓘ Opal	SiO₂ · nH₂O
O	ⓘ Quartz	SiO₂
O	ⓘ Stilbite Subgroup	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O
O	ⓘ Heulandite-Ca	(Ca,Na)₅(Si₂₇Al₉)O₇₂ · 26H₂O
O	ⓘ Heulandite-Na	(Na,Ca,K)₆(Si,Al)₃₆O₇₂ · 22H₂O
O	ⓘ Stilbite-Ca	NaCa₄(Si₂₇Al₉)O₇₂ · 28H₂O
Na	Sodium
Na	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
Na	ⓘ Mordenite	(Na₂,Ca,K₂)₄(Al₈Si₄₀)O₉₆ · 28H₂O
Na	ⓘ Heulandite-Ca	(Ca,Na)₅(Si₂₇Al₉)O₇₂ · 26H₂O
Na	ⓘ Heulandite-Na	(Na,Ca,K)₆(Si,Al)₃₆O₇₂ · 22H₂O
Na	ⓘ Stilbite-Ca	NaCa₄(Si₂₇Al₉)O₇₂ · 28H₂O
Mg	Magnesium
Mg	ⓘ Augite	(Ca_xMg_yFe_z)(Mg_y1Fe_z1)Si₂O₆
Al	Aluminium
Al	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
Al	ⓘ Laumontite	CaAl₂Si₄O₁₂ · 4H₂O
Al	ⓘ Mordenite	(Na₂,Ca,K₂)₄(Al₈Si₄₀)O₉₆ · 28H₂O
Al	ⓘ Stilbite Subgroup	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O
Al	ⓘ Heulandite-Ca	(Ca,Na)₅(Si₂₇Al₉)O₇₂ · 26H₂O
Al	ⓘ Heulandite-Na	(Na,Ca,K)₆(Si,Al)₃₆O₇₂ · 22H₂O
Al	ⓘ Stilbite-Ca	NaCa₄(Si₂₇Al₉)O₇₂ · 28H₂O
Si	Silicon
Si	ⓘ Quartz var. Agate	SiO₂
Si	ⓘ Quartz var. Amethyst	SiO₂
Si	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
Si	ⓘ Augite	(Ca_xMg_yFe_z)(Mg_y1Fe_z1)Si₂O₆
Si	ⓘ Quartz var. Chalcedony	SiO₂
Si	ⓘ Opal var. Opal-AN	SiO₂ · nH₂O
Si	ⓘ Laumontite	CaAl₂Si₄O₁₂ · 4H₂O
Si	ⓘ Mordenite	(Na₂,Ca,K₂)₄(Al₈Si₄₀)O₉₆ · 28H₂O
Si	ⓘ Opal	SiO₂ · nH₂O
Si	ⓘ Quartz	SiO₂
Si	ⓘ Stilbite Subgroup	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O
Si	ⓘ Heulandite-Ca	(Ca,Na)₅(Si₂₇Al₉)O₇₂ · 26H₂O
Si	ⓘ Heulandite-Na	(Na,Ca,K)₆(Si,Al)₃₆O₇₂ · 22H₂O
Si	ⓘ Stilbite-Ca	NaCa₄(Si₂₇Al₉)O₇₂ · 28H₂O
K	Potassium
K	ⓘ Mordenite	(Na₂,Ca,K₂)₄(Al₈Si₄₀)O₉₆ · 28H₂O
K	ⓘ Heulandite-Na	(Na,Ca,K)₆(Si,Al)₃₆O₇₂ · 22H₂O
Ca	Calcium
Ca	ⓘ Augite	(Ca_xMg_yFe_z)(Mg_y1Fe_z1)Si₂O₆
Ca	ⓘ Calcite	CaCO₃
Ca	ⓘ Laumontite	CaAl₂Si₄O₁₂ · 4H₂O
Ca	ⓘ Mordenite	(Na₂,Ca,K₂)₄(Al₈Si₄₀)O₉₆ · 28H₂O
Ca	ⓘ Heulandite-Ca	(Ca,Na)₅(Si₂₇Al₉)O₇₂ · 26H₂O
Ca	ⓘ Heulandite-Na	(Na,Ca,K)₆(Si,Al)₃₆O₇₂ · 22H₂O
Ca	ⓘ Stilbite-Ca	NaCa₄(Si₂₇Al₉)O₇₂ · 28H₂O
Fe	Iron
Fe	ⓘ Augite	(Ca_xMg_yFe_z)(Mg_y1Fe_z1)Si₂O₆

Other Regions, Features and Areas containing this locality

North AmericaContinent

Rocky MountainsMountain Range

North America PlateTectonic Plate

USA

Western Phosphate fieldMineral Province

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

Ream, Lanny (2001) Mineral News: 17(8): 5.

Ream, Lanny R. (2004) Idaho Minerals - The Complete Reference and Guide to the Minerals of Idaho. (2nd ed.) Museum of Northern Idaho. 373pp.

Cornish, John, (2005) Fluorescent Zeolites and Associated Minerals from the Rat's Nest Mine, Challis, Idaho (January 7, 2005): 2.

www.christuckerminerals.com (2007) http://www.christuckerminerals.com/rats_nest.htm

www.mindat.org (2016) http://www.mindat.org/mesg-7-307477.html

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List of minerals arranged by Strunz 10th Edition classification

List of minerals for each chemical element

Other Regions, Features and Areas containing this locality

References

Rat's Nest claim, Custer County, Idaho, USA i
Regional Level Types
Rat's Nest claim Claim
Custer County County
Idaho State
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