7 miles west of Terlingua

Structure: Breccia Pipe

Alteration: Kaolinization Of Del Rio Clay

Deposit: Deposits occur as lodes related to solution collapse along the santa elena limestone-del rio clay contact, calcite veins in the boquillas formation and buda limestone, solution-collapse breccia pipes in the santa elena limestone, del rio clay, buda limestone, and boquillas formation, lodes along santa elena-del rio contact, and fracture fillings in tertiary rhyolite intrusives. Cinnabar replaces clay matrix of a solution-collapse breccia pipe; some calcite-cinnabar veins this record includes data from duplicate record m055137 by joel r. Bergquist (73 09) which has been deleted.

Development: Deposits mined by comanche indians for war paint. Known to locals As early As 1840. First production of mercury in 1888. Prospected during and before world war i. ; econ.com: lone star mercury co. Installed a 35 st/d gould furnace 1956 to produce 40 to 50 flasks hg per week.

Geology: Thick sequences of cret limestones and shales are cut by n W striking normal faults with hundreds of feet of displacement border long narrow grabens and smaller magnitude N W trending faults. Tert basalt and trachyte sills, plugs and laccoliths are prominent. The terlingua anticline is possibly underlain by a laccolithic intrusion. ; geol.desc: thick sequences of cret. Limestones and shales are cut by n W striking normal faults with hundreds of feet of displacement border long narrow grabens and smaller magnitude n W trending faults. Tertiary basalt and trachyte sills, plugs and laccoliths are prominent. The terlingua anticline is possibly underlain by a laccolithic intrusion. Breccia pipe enclosed in devils river limestone and containing fragments of boquillas flags buda limestone and chisos fm set in a clay matrix of the grayson fm (cret). All units except chisos volcanics are cret. Chisos volcanics are tertiary.

Rock formation(s): Santa Elena Limestone

Ore(s): Breccia Pipe In Limestone

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.

ⓘ Mercury

Mineral List

ⓘ Calcite

ⓘ Cinnabar

2 valid minerals.

Rock Types Recorded

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

Select Rock List Type

Alphabetical List Tree Diagram

ⓘ Limestone

ⓘ Volcanic breccia

Detailed Mineral List:

ⓘ Calcite

Formula: CaCO₃

References:

Smith, Arthur E. (1991) Texas Mineral Locality Index. Rocks & Minerals, 66 (3) 196-224 doi:10.1080/00357529.1991.11761622

ⓘ Cinnabar

Formula: HgS

References:

Smith, Arthur E. (1991) Texas Mineral Locality Index. Rocks & Minerals, 66 (3) 196-224 doi:10.1080/00357529.1991.11761622

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘ	Cinnabar	2.CD.15a	HgS
Group 5 - Nitrates and Carbonates
ⓘ	Calcite	5.AB.05	CaCO₃

List of minerals for each chemical element

C	Carbon
C	ⓘ Calcite	CaCO₃
O	Oxygen
O	ⓘ Calcite	CaCO₃
S	Sulfur
S	ⓘ Cinnabar	HgS
Ca	Calcium
Ca	ⓘ Calcite	CaCO₃
Hg	Mercury
Hg	ⓘ Cinnabar	HgS

Other Databases

Link to USGS MRDS:	10040387

Other Regions, Features and Areas containing this locality

North AmericaContinent

North America PlateTectonic Plate

USA

Texas
- Terlingua Mining DistrictMining District

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

EXAMINED BY R.G. YATES AND OTHERS, (1942)-1945

MINING WORLD, (1955), SEPT. P. 108.

MINING WORLD, (1956), VOL. 18., NO. 4, P. 81

CHESTER, J.W., (1965), MERCURY IN TEXAS: USBM IC 8252

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