Kariminia, S. M., Pickering, S. M., Kogel, J. E., Elliott, W. C., Simmons, R., & Ghazi, A. M. (2001). Preliminary Facies Analysis of the Twiggs Clay Formation at the Sara Dukes Mine, Sandersville, Georgia. GSA Southeastern Section - 50th Annual Meeting (April 5-6, 2001)

ⓘ Kaolinite

Formula: Al₂(Si₂O₅)(OH)₄

Localities: Reported from at least 53 localities in this region.

ⓘ Opal

Formula: SiO₂ · nH₂O

Localities:

Dick Warthen property, Warthen, Washington County, Georgia, USA
Washington County, Georgia, USA

ⓘ Opal var. Fire Opal ?

Formula: SiO₂ · nH₂O

References:

(1917) Useful minerals of the United States. Bulletin 624. US Geological Survey doi:10.3133/b624

ⓘ 'Smectite Group'

Formula: A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O

Locality: Sara Dukes Mine, Sandersville, Washington County, Georgia, USA

References:

ⓘ Zircon

Formula: Zr(SiO₄)

Locality: Riddleville, Washington County, Georgia, USA

References:

Geochimica et Cosmochimica Acta Volume 59, Issue 19, October 1995, Pages 4071-4082

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘ	Opal	4.DA.10	SiO₂ · nH₂O
ⓘ	var. Fire Opal ?	4.DA.10	SiO₂ · nH₂O
ⓘ	Baddeleyite	4.DE.35	ZrO₂
Group 9 - Silicates
ⓘ	Zircon	9.AD.30	Zr(SiO₄)
ⓘ	Kaolinite	9.ED.05	Al₂(Si₂O₅)(OH)₄
Unclassified
ⓘ	'Clay minerals'	-
ⓘ	'Smectite Group'	-	A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Kaolinite	Al₂(Si₂O₅)(OH)₄
H	ⓘ Opal	SiO₂ · nH₂O
H	ⓘ Opal var. Fire Opal	SiO₂ · nH₂O
H	ⓘ Smectite Group	A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O
O	Oxygen
O	ⓘ Baddeleyite	ZrO₂
O	ⓘ Kaolinite	Al₂(Si₂O₅)(OH)₄
O	ⓘ Opal	SiO₂ · nH₂O
O	ⓘ Zircon	Zr(SiO₄)
O	ⓘ Opal var. Fire Opal	SiO₂ · nH₂O
O	ⓘ Smectite Group	A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O
Al	Aluminium
Al	ⓘ Kaolinite	Al₂(Si₂O₅)(OH)₄
Si	Silicon
Si	ⓘ Kaolinite	Al₂(Si₂O₅)(OH)₄
Si	ⓘ Opal	SiO₂ · nH₂O
Si	ⓘ Zircon	Zr(SiO₄)
Si	ⓘ Opal var. Fire Opal	SiO₂ · nH₂O
Zr	Zirconium
Zr	ⓘ Baddeleyite	ZrO₂
Zr	ⓘ Zircon	Zr(SiO₄)

Fossils

There are 3 fossil localities from the PaleoBioDB database within this region.

These data are provided on an experimental basis and are taken from external databases. Mindat.org has no control currently over the accuracy of these data.

Occurrences

Youngest Fossil Listed

33.9 Ma (Oligocene)

Oldest Fossil Listed

56.0 Ma (Paleocene)

Stratigraphic Units

Unit	No. Occurrences	Age
Tobacco Road - Sandersville	1	38 - 33.9 Ma (Paleogene)

Fossils from Region

Click here to show the list.

Accepted Name	Hierarchy	Age
Basilosauridae family	Animalia : Chordata : Mammalia : Cetacea : Basilosauridae	38 - 33.9 Ma Paleogene
Dugongidae family	Animalia : Chordata : Mammalia : Sirenia : Dugongidae	38 - 33.9 Ma Paleogene
Periarchus quinquefarius species	Animalia : Echinodermata : Echinoidea : Clypeasteroida : Protoscutellidae : Periarchus : *Periarchus quinquefarius*	56 - 33.9 Ma Paleogene

Fossil Localities

Click to show 3 fossil localities

USA

Georgia
- Washington County
  - Paleogene🐚 Sandersville
  - Paleogene🐚 Tennile Lime Sinks
  - Paleogene🐚 Warthen

Other Databases

Wikipedia:	https://en.wikipedia.org/wiki/Washington_County,_Georgia
Wikidata ID:	Q498286
GeoNames ID:	4229557

Localities in this Region

USA

Georgia
- Washington County

USA

Georgia
- Washington County

Other Regions, Features and Areas that Intersect

North AmericaContinent

North America PlateTectonic Plate

Charleston ArcVolcanic Arc
Charleston DomainDomain
Newark Group BasinsBasin

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List of minerals arranged by Strunz 10th Edition classification

List of minerals for each chemical element

Fossils

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