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Skull Springs, Malheur County, Oregon, USAi
Regional Level Types
Skull SpringsDiggings (Active)
Malheur CountyCounty
OregonState
USACountry

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PhotosMapsSearch
05993520017361177692981.jpg
Thunder Egg, etc.

Skull Springs, Malheur County, Oregon, USA
05993520017361177692981.jpg
Thunder Egg, etc.

Skull Springs, Malheur County, Oregon, USA
05993520017361177692981.jpg
Thunder Egg, etc.

Skull Springs, Malheur County, Oregon, USA
Latitude & Longitude:
43° North , 117° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~142km
GRN:
N29W63
Type:
Diggings (Active) - last checked 2024
Mindat Locality ID:
445255
Long-form identifier:
mindat:1:2:445255:6
GUID (UUID V4):
0
Other/historical names associated with this locality:
Dry Creek beds, Juntura beds, Harper beds


The Skull Springs site is a thunderegg locality (thunderegg beds) in eastern Oregon near the town of Harper. Skull Springs Thundereggs are characterized by reddish-brown rhyolitic shells and by cores containing hydrothermal brecciated agate/chalcedony, parallel banding, and/or common white opal. The thundereggs from here tend to be large and may range up to ~3.5 ft in diameter. Historically, the thunderegg beds at this locality have also been called the Dry Creek beds, Juntura beds, Harper beds.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


2 valid minerals.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

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Alphabetical List Tree Diagram

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz
var. Agate		4.DA.05SiO2
ⓘvar. Chalcedony4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘOpal4.DA.10SiO2 · nH2O

List of minerals for each chemical element

HHydrogen
Hⓘ OpalSiO2 · nH2O
OOxygen
Oⓘ Quartz var. AgateSiO2
Oⓘ Quartz var. ChalcedonySiO2
Oⓘ OpalSiO2 · nH2O
Oⓘ QuartzSiO2
SiSilicon
Siⓘ Quartz var. AgateSiO2
Siⓘ Quartz var. ChalcedonySiO2
Siⓘ OpalSiO2 · nH2O
Siⓘ QuartzSiO2

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

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

L. Johnson, Rockhounding Oregon (A Falcon Guide), ©2014, pg 221.
Colburn, R. (2004) The Formation of Thundereggs (Lithophysae). 2004 revision, pp 219, 362, 439.
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