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Polka Dot Agate mine, Jefferson County, Oregon, USAi
Regional Level Types
Polka Dot Agate mineMine
Jefferson CountyCounty
OregonState
USACountry

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PhotosMapsSearchMineralogy
04795250017272054104089.jpg
Main Pit at the Canyon Rim Thunderegg Deposit, Priday Polka Dot Beds, Jefferson Co., OR

Polka Dot Agate mine, Jefferson County, Oregon, USA
00486860017272054129165.jpg
Typical Large Thunderegg Showing Botryoidal/Stalactic Chalcedony Forms at the Canyon Rim Deposit, Jefferson Co., OR

Polka Dot Agate mine, Jefferson County, Oregon, USA
00821140017272267146575.jpg
View from the Floor of the Main Pit at the Polka Dot Agate Deposit, Jefferson Co., OR

Polka Dot Agate mine, Jefferson County, Oregon, USA
04795250017272054104089.jpg
Main Pit at the Canyon Rim Thunderegg Deposit, Priday Polka Dot Beds, Jefferson Co., OR

Polka Dot Agate mine, Jefferson County, Oregon, USA
00486860017272054129165.jpg
Typical Large Thunderegg Showing Botryoidal/Stalactic Chalcedony Forms at the Canyon Rim Deposit, Jefferson Co., OR

Polka Dot Agate mine, Jefferson County, Oregon, USA
00821140017272267146575.jpg
View from the Floor of the Main Pit at the Polka Dot Agate Deposit, Jefferson Co., OR

Polka Dot Agate mine, Jefferson County, Oregon, USA
04795250017272054104089.jpg
Main Pit at the Canyon Rim Thunderegg Deposit, Priday Polka Dot Beds, Jefferson Co., OR

Polka Dot Agate mine, Jefferson County, Oregon, USA
00486860017272054129165.jpg
Typical Large Thunderegg Showing Botryoidal/Stalactic Chalcedony Forms at the Canyon Rim Deposit, Jefferson Co., OR

Polka Dot Agate mine, Jefferson County, Oregon, USA
Latitude & Longitude (WGS84):
44° 45' 37'' North , 120° 49' 45'' West
Latitude & Longitude (decimal):
44.76047,-120.82927
GRN:
N30W63
Type:
Mine
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Madras6,662 (2017)27.6km
Metolius743 (2017)33.7km
Warm Springs2,945 (2011)34.5km
Culver1,442 (2017)40.0km
Maupin430 (2017)50.2km
Mindat Locality ID:
150986
Long-form identifier:
mindat:1:2:150986:4
GUID (UUID V4):
0
Other/historical names associated with this locality:
Priday Polka Dot Beds


The Polka Dot Agate Mine is known for Agates with "Polka Dot" inclusions containing Limonite or Hematite. Canyon Rim produces Thundereggs containing Agate and Chalcedony.

Commodities (Major) - Gemstone - Semiprecious
Development Status: Producer

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


2 valid minerals.

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
ⓘvar. Polka Dot Agate4.DA.05SiO2
ⓘOpal4.DA.10SiO2 · nH2O
Unclassified
ⓘ'Limonite'-

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 Databases

Link to USGS MRDS:10274484

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

(Gem Trails Of Oregon Garret Romaine)
U.S. BUREAU OF MINES (1994), DIRECTORY OF PRINCIPAL U.S. GEMSTONE PRODUCERS IN 1993, U.S. BUREAU OF MINES MINERAL INDUSTRY SURVEYS: 48.
Zenz, Johann (2009) Madras, Oregon, USA: "Polka Dot" - ein ungewöhnliches Gangachat-Vorkommen [Madras, Oregon, USA: "Polka Dot" - an unusual gangue agate deposit]. Mineralien Welt, 20 (4). p.88-96.
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