A former surface gypsum and diatomaceous earth mine located in secs. 13 & 24, T9S, R17E, and in secs. 17-20, 29 & 30, T9S, R18E on the E bank of the San Pedro River about 2 miles downstream from Whitlock Wash. Produced 1920's to 1940's. The property extends into secs. 17, 18, 20, 29 & 30, and into secs. 13 & 24, T9S, R18E. Owned by the University of Arizona. Operated by Arimetco International, Inc. (1992). Previous operators included the White Cliffs, Inc. (1989).

Mineralization is a lacustrine diatomite and gypsum deposit hosted in the Quiburis Formation (Mudstone, siltstone, chert, diatomite, tuff). The diatomaceous sedimentary sequence, which contains abundant layers of mudstone, siltstone, and tuffaceous material, is at least 140 feet (42.67 meters) thick, 3218.6 meters wide and 4827.9 meters long. These strata have been faulted and folded and are tilted a few degrees to the NE and are truncated at the top by an erosional surface. The erosianal surface also cuts out older units to the SW. Locally, the diatomaceous sediment grades 60% - 80% diatomite.

The ash beds in the central part of the White Cliffs area are not commonly altered, although one bed in Camel Canyon has been altered to bentonite. No zeolites have been identified in the immediate area.

Workings include many small quarries which were put in during the 1960's. Kaiser put in 12 drill holes in 1968 around the periphery of the deposit. There has been "considerable" production in the past. This is the only Arizona deposit with a significant production history. Arimetco planned to begin production in February, 1993. This deposit is selectively mined for 1 foot to 2 feet thick beds of diatomite.

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Standard Detailed Gallery Strunz Chemical Elements

Commodity List

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

ⓘ Gypsum & Anhydrite

Mineral List

ⓘ Calcite

ⓘ Gypsum

ⓘ Opal

3 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

ⓘ 'Bentonite'

ⓘ Chert

ⓘ Diatomite

Detailed Mineral List:

ⓘ Calcite

Formula: CaCO₃

References:

Collected by Ed Pedersen and Dan Vice in 1968/9

ⓘ Gypsum

Formula: CaSO₄ · 2H₂O

References:

MRDS database Dep. ID #10060239, MRDS ID #TC10208.

ⓘ Opal

Formula: SiO₂ · nH₂O

References:

MRDS database Dep. ID #10060239, MRDS ID #TC10208.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘ	Opal	4.DA.10	SiO₂ · nH₂O
Group 5 - Nitrates and Carbonates
ⓘ	Calcite	5.AB.05	CaCO₃
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘ	Gypsum	7.CD.40	CaSO₄ · 2H₂O

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Gypsum	CaSO₄ · 2H₂O
H	ⓘ Opal	SiO₂ · nH₂O
C	Carbon
C	ⓘ Calcite	CaCO₃
O	Oxygen
O	ⓘ Calcite	CaCO₃
O	ⓘ Gypsum	CaSO₄ · 2H₂O
O	ⓘ Opal	SiO₂ · nH₂O
Si	Silicon
Si	ⓘ Opal	SiO₂ · nH₂O
S	Sulfur
S	ⓘ Gypsum	CaSO₄ · 2H₂O
Ca	Calcium
Ca	ⓘ Calcite	CaCO₃
Ca	ⓘ Gypsum	CaSO₄ · 2H₂O

Other Databases

Link to USGS MRDS:	10060239

Other Regions, Features and Areas containing this locality

Mexico

Sierra Madre OccidentalMountain Range

North AmericaContinent

Sonoran DesertDesert
- San Pedro river valleyValley

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

Arizona Department of Mineral Resources Whitecliffs Mine file.

Arizona Department of Mineral Resources Mammoth Mining and Minerals Inc. file.

Arizona Department of Mineral Resources Azo Mined Products Co. Inc. file.

Arizona Department of Mineral Resources U file.

USGS Clark Ranch Quadrangle map.

MRDS database Dep. ID #10060239, MRDS ID #TC10208; and Dep. ID #10210795, MAS ID #0040210883.

Wilson, E.D. (1944), Arizona nonmetallics: A summary of past production and present operations, Arizona Bureau of Mines Bull. 152: 18.

Peirce, H.W. (1969), Diatomite, in USGS & Arizona Bureau of Mines & U.S. Bureau of Reclamation, Mineral and Water Resources of Ariaona, Arizona Bureau of Mines Bull. 180 (USGS Bull.871): 337-342.

Elevatorski, E.A. (1980) Arizona Industrial Minerals: 54.

Phillips, K.A. (1987), Arizona Industrial Minerals, 2nd. Edition, Arizona Department of Mines & Minerals Min. Report 4, 185 pp.

Peirce, H.W. (1989) Arizona Geological Survey Industrial Mineral card files.

Phillips, K.A., Niemuth, N.J., and Bain, D.R. (1992) Active Mines in Arizona – 1993: Arizona Department of Mines and Mineral Resources Directory 40, 25 pp.

Shenk, J.D. (1992) Geology of the White Cliffs Diatomite Deposit and Aravaipa Creek Gypsum Deposit, Lower San Pedro Valley, Arizona, in: Houser. B.B., Editor, Industrial Minerals of the Tucson Area and San pedro Valley, Southeastern Arizona: Tucson, Arizona Geological Society Field trip, April 4-5, 1992, Guidebook: 37-47.

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White Cliffs Mine, Whitlock Wash area, Pinal County, Arizona, USAiRegional Level TypesWhite Cliffs MineMine Whitlock Wash areaArea Pinal CountyCounty ArizonaState USACountry function showexplain() { $("#locexplain").toggle(); if (typeof movemap === "function") movemap(); }

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Commodity List

Mineral List

Rock Types Recorded

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Detailed Mineral List:

Gallery:

List of minerals arranged by Strunz 10th Edition classification

List of minerals for each chemical element

Other Databases

Other Regions, Features and Areas containing this locality

References

White Cliffs Mine, Whitlock Wash area, Pinal County, Arizona, USA i
Regional Level Types
White Cliffs Mine Mine
Whitlock Wash area Area
Pinal County County
Arizona State
USA Country