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Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA i
Regional Level Types
Elk Rock Island Island
Milwaukie City
Clackamas County County
Oregon State
USA Country

Regional Level Types
Elk Rock Island	Island
Milwaukie	City
Clackamas County	County
Oregon	State
USA	Country

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Smectite Group, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Lévyne, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Smectite Group, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Smectite Group, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Lévyne, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Smectite Group, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Smectite Group, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Lévyne, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Latitude & Longitude (WGS84):

45° 26' 9'' North , 122° 38' 52'' West

Latitude & Longitude (decimal):

G#: c20f3p6kn

Type:

Köppen climate type:

Csb : Warm-summer Mediterranean climate

Mindat Locality ID:

19926

Long-form identifier:

mindat:1:2:19926:4

GUID (UUID V4):

Zeolites and smectite are found in the Miocene Columbia River basalt exposed during low water along the southern and eastern sides of Elk Island in the middle of the Willamette River in Milwaukie, Clackamas County, Oregon. Minerals were first found by Gordon Gilbertson in 1975 in boulders near the island. The collecting site can only be reached during low water in the summer along with low tide that backs up the river. The most unusual mineral combination is an overgrowth of gray-green smectite that covers thin hexagonal levyne/offretite crystals forming incrustation pseudomorphs. Rudy Tschernich

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

ⓘ Analcime

ⓘ 'Chabazite'

ⓘ 'Heulandite Subgroup'

ⓘ 'Lévyne'

ⓘ Offretite

ⓘ 'Smectite Group'

ⓘ 'Stilbite Subgroup'

2 valid minerals.

Detailed Mineral List:

ⓘ Analcime

Formula: Na(AlSi₂O₆) · H₂O

References:

Micro Probe Volume VI Number 4

ⓘ 'Chabazite'

References:

Micro Probe Volume VI Number 4

ⓘ 'Heulandite Subgroup'

Formula: (Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂O

References:

(n.d.) Rudy Tschernich Zeolite Collection, Rice Museum.

ⓘ 'Lévyne'

References:

Micro Probe Volume VI Number 4

ⓘ Offretite

Formula: KCaMg(Si₁₃Al₅)O₃₆ · 15H₂O

References:

Micro Probe Volume VI Number 4

ⓘ 'Smectite Group'

Formula: A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O

References:

(n.d.) Rudy Tschernich Zeolite Collection, Rice Museum.

ⓘ 'Stilbite Subgroup'

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

References:

Micro Probe Volume VI Number 4

Gallery:

(Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂Oⓘ 'Heulandite Subgroup'

Heulandite Subgroup, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Heulandite Subgroup, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Heulandite Subgroup, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Heulandite Subgroup, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Heulandite Subgroup, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Heulandite Subgroup, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

KCaMg(Si₁₃Al₅)O₃₆ · 15H₂Oⓘ Offretite

Offretite, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Offretite, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Offretite, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Offretite, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Offretite, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

Offretite, etc.

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA

List of minerals arranged by Strunz 10th Edition classification

Group 9 - Silicates
ⓘ	Analcime	9.GB.05	Na(AlSi₂O₆) · H₂O
ⓘ	Offretite	9.GD.25	KCaMg(Si₁₃Al₅)O₃₆ · 15H₂O
Unclassified
ⓘ	'Chabazite'	-
ⓘ	'Heulandite Subgroup'	-	(Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂O
ⓘ	'Lévyne'	-
ⓘ	'Stilbite Subgroup'	-	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O
ⓘ	'Smectite Group'	-	A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
H	ⓘ Heulandite Subgroup	(Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂O
H	ⓘ Offretite	KCaMg(Si₁₃Al₅)O₃₆ · 15H₂O
H	ⓘ Stilbite Subgroup	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O
H	ⓘ Smectite Group	A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O
O	Oxygen
O	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
O	ⓘ Heulandite Subgroup	(Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂O
O	ⓘ Offretite	KCaMg(Si₁₃Al₅)O₃₆ · 15H₂O
O	ⓘ Stilbite Subgroup	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O
O	ⓘ Smectite Group	A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O
Na	Sodium
Na	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
Na	ⓘ Heulandite Subgroup	(Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂O
Mg	Magnesium
Mg	ⓘ Offretite	KCaMg(Si₁₃Al₅)O₃₆ · 15H₂O
Al	Aluminium
Al	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
Al	ⓘ Heulandite Subgroup	(Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂O
Al	ⓘ Offretite	KCaMg(Si₁₃Al₅)O₃₆ · 15H₂O
Al	ⓘ Stilbite Subgroup	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O
Si	Silicon
Si	ⓘ Analcime	Na(AlSi₂O₆) · H₂O
Si	ⓘ Heulandite Subgroup	(Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂O
Si	ⓘ Offretite	KCaMg(Si₁₃Al₅)O₃₆ · 15H₂O
Si	ⓘ Stilbite Subgroup	M_6-7[Al_8-9Si_27-28O₇₂] · nH₂O
K	Potassium
K	ⓘ Heulandite Subgroup	(Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂O
K	ⓘ Offretite	KCaMg(Si₁₃Al₅)O₃₆ · 15H₂O
Ca	Calcium
Ca	ⓘ Heulandite Subgroup	(Na/Ca/K)_5-6[Al_8-9 Si_27-28 O₇₂] · nH₂O
Ca	ⓘ Offretite	KCaMg(Si₁₃Al₅)O₃₆ · 15H₂O

Other Regions, Features and Areas containing this locality

North AmericaContinent

North America PlateTectonic Plate

Cascade ArcVolcanic Arc
Siletzia DomainDomain
Western Washington–Oregon BasinsBasin

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

Tschernich, R.W. (1987) Selected zeolite locations in the Pacific Northwest. Micro Probe, V 6, No. 4, pp. 3-27.

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Elk Rock Island, Milwaukie, Clackamas County, Oregon, USAiRegional Level TypesElk Rock IslandIsland MilwaukieCity Clackamas CountyCounty OregonState USACountry function showexplain() { $("#locexplain").toggle(); if (typeof movemap === "function") movemap(); }

Select Mineral List Type

Mineral List

Detailed Mineral List:

Gallery:

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

Elk Rock Island, Milwaukie, Clackamas County, Oregon, USA i
Regional Level Types
Elk Rock Island Island
Milwaukie City
Clackamas County County
Oregon State
USA Country