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Williamson County, Texas, USA i
Regional Level Types
Williamson County County
Texas State
USA Country

Regional Level Types
Williamson County	County
Texas	State
USA	Country

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Predictive Mineralogy

Calcite

Williamson County, Texas, USA

Calcite

Williamson County, Texas, USA

Calcite

Williamson County, Texas, USA

Calcite

Williamson County, Texas, USA

Calcite

Williamson County, Texas, USA

Calcite

Williamson County, Texas, USA

Calcite

Williamson County, Texas, USA

Calcite

Williamson County, Texas, USA

Neighbouring regions:

Burnet County, Texas, USA

Travis County, Texas, USA

Bastrop County, Texas, USA

Bell County, Texas, USA

Lee County, Texas, USA

Milam County, Texas, USA

Type:

County

Largest Settlements:

Place	Population
Round Rock	115,997 (2017)
Cedar Park	65,945 (2017)
Georgetown	63,716 (2017)
Leander	37,889 (2017)
Hutto	22,722 (2017)
Brushy Creek	21,764 (2011)

Mindat Locality ID:

216294

Long-form identifier:

mindat:1:2:216294:5

GUID (UUID V4):

Other Languages:

View 37 more...

French:

comté de Williamson, Texas, États-Unis

German:

Williamson County, Texas, Vereinigte Staaten

Italian:

contea di Williamson, Texas, Stati Uniti d'America

Russian:

Уильямсон, Техас, Соединённые Штаты Америки

Simplified Chinese:

威廉森縣, 德克萨斯州, 美国

Spanish:

Condado de Williamson, Texas, Estados Unidos

Albanian:

Williamson County, Texas, Shtetet e Bashkuara të Amerikës

Arabic:

مقاطعة ويليامسون , تكساس, الولايات المتحدة

Armenian:

Վիլյամսոն շրջան, Տեխաս, Ամերիկայի Միացյալ Նահանգներ

Basque:

Williamson konderria , Texas

Bavarian:

Williamson County, Texas, Vaoanigte Stootn

Bishnupriya Manipuri:

উইলিয়ামসন কাউন্টি, টেক্সাস, তিলপারাষ্ট্র

Bulgarian:

Уилиямсън, Тексас, Съединени американски щати

Cebuano:

Williamson County , Texas

Czech:

Williamson County, Texas, Spojené státy americké

Dutch:

Williamson County, Texas, Verenigde Staten

Estonian:

Williamsoni maakond , Texas, Ameerika Ühendriigid

Farsi/Persian:

شهرستان ویلیامسون، تگزاس, تگزاس, ایالات متحده آمریکا

Georgian:

უილიამსონის ოლქი, ტეხასი, ამერიკის შეერთებული შტატები

Hebrew:

מחוז ויליאמסון, טקסס, ארצות הברית

Hungarian:

Williamson megye, Texas, Amerikai Egyesült Államok

Irish Gaelic:

Contae Williamson, Texas, Stáit Aontaithe Mheiriceá

Japanese:

ウィリアムソン郡, テキサス州, アメリカ合衆国

Latin:

Williamson Comitatus, Texia, Civitates Foederatae Americae

Low Saxon/Low German:

Williamson County, Texas, USA

Macedonian:

Вилијамсон, Тексас, Соединети Американски Држави

Min Dong Chinese:

Williamson Gông, Texas

Minnan / Hokkien-Taiwanese:

Williamson Kūn

Norwegian:

Williamson County, Texas, USA

Polish:

Hrabstwo Williamson, Teksas, Stany Zjednoczone

Portuguese:

Condado de Williamson, Texas, Estados Unidos

Romanian:

Comitatul Williamson, Texas, Statele Unite ale Americii

Sardinian:

contea de Williamson, Texas, Istados Unidos de Amèrica

Serbian:

Округ Вилијамсон, Тексас, Сједињене Америчке Државе

Serbo-Croatian:

Williamson County, Texas, Sjedinjene Američke Države

Swedish:

Williamson County, Texas, USA

Traditional Chinese:

威廉森縣, 德薩斯州, 美國

Turkish:

Williamson County, Teksas, Amerika Birleşik Devletleri

Ukrainian:

Вільямсон, Техас, Сполучені Штати Америки

Urdu:

ولیمسن کاؤنٹی، ٹیکساس, ٹیکساس, ریاستہائے متحدہ امریکا

Vietnamese:

Quận Williamson, Texas, Chủng Quốc Hoa Kỳ

Waray:

Condado han Williamson, Texas, Estados Unidos

Western Punjabi:

ولیمسن کاؤنٹی، ٹیکساس, ٹیکساس, امریکہ

No description has been added for this locality. Can you add one?

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded from this region.

ⓘ Iron pyrite

ⓘ Mineral specimens

Mineral List

Mineral list contains entries from the region specified including sub-localities

11 valid minerals.

Rock Types Recorded

Rock list contains entries from the region specified including sub-localities

Select Rock List Type

Alphabetical List Tree Diagram

ⓘ H3 chondrite meteorite

Detailed Mineral List:

ⓘ Aragonite

Formula: CaCO₃

Locality: Interstate highway 35 - highway 29 roadcut, Georgetown, Williamson County, Texas, USA

References:

personally collected - Bill Morgenstern

ⓘ Calcite

Formula: CaCO₃

Localities: Reported from at least 6 localities in this region.

ⓘ Celestine

Formula: SrSO₄

Locality: South Fork San Gabriel River occurrence, Georgetown, Williamson County, Texas, USA

References:

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

ⓘ Chromite

Formula: Fe²⁺Cr³⁺₂O₄

Locality: Florence meteorite, Florence, Williamson County, Texas, USA

References:

Lonsdale, John T. (1927) The Florence Meteorite of Williamson County, Texas. American Mineralogist, 12 (11) 398-404

ⓘ 'Fayalite-Forsterite Series'

Locality: Florence meteorite, Florence, Williamson County, Texas, USA

Description: Ave. composition (Fa17) places Florence within the H chondrite group (Mason, 1963).

References:

Lonsdale, John T. (1927) The Florence Meteorite of Williamson County, Texas. American Mineralogist, 12 (11) 398-404

Mason, Brian (1963) Olivine composition in chondrites. Geochimica et Cosmochimica Acta, 27 (10) 1011-1023 doi:10.1016/0016-7037(63)90062-0

ⓘ Marcasite

Formula: FeS₂

Locality: Round Rock, Williamson County, Texas, USA

References:

Bill Morgenstern - Collection

ⓘ Native Gold

Formula: Au

References:

Garner,L.Edwin (2010) Mineral Resources and Mining :The Handbook of Texas Online

ⓘ Native Iron

Formula: Fe

Locality: Florence meteorite, Florence, Williamson County, Texas, USA

References:

Lonsdale, John T. (1927) The Florence Meteorite of Williamson County, Texas. American Mineralogist, 12 (11) 398-404

ⓘ Native Iron var. Kamacite

Formula: (Fe,Ni)

Locality: Florence meteorite, Florence, Williamson County, Texas, USA

References:

Lonsdale, John T. (1927) The Florence Meteorite of Williamson County, Texas. American Mineralogist, 12 (11) 398-404

ⓘ 'Orthopyroxene Subgroup'

Locality: Florence meteorite, Florence, Williamson County, Texas, USA

References:

Keil, Klaus, Fredriksson, Kurt (1964) The iron, magnesium, and calcium distribution in coexisting olivines and rhombic pyroxenes of chondrites. Journal of Geophysical Research, 69 (16) 3487-3515 doi:10.1029/jz069i016p03487

ⓘ 'Plagioclase'

Formula: (Na,Ca)[(Si,Al)AlSi₂]O₈

Locality: Florence meteorite, Florence, Williamson County, Texas, USA

References:

Lonsdale, John T. (1927) The Florence Meteorite of Williamson County, Texas. American Mineralogist, 12 (11) 398-404

ⓘ Pyrite

Formula: FeS₂

Locality: Inner Space Cavern (Laubach Cave), Georgetown, Williamson County, Texas, USA

References:

Onac, Bogdan P. (2025) Cave minerals of the 21st century: A 2025 review and update. International Journal of Speleology, 54 (1). ijs2552 doi:10.5038/1827-806x.ijs2552

ⓘ 'Pyroxene Group'

Formula: ADSi₂O₆

Locality: Florence meteorite, Florence, Williamson County, Texas, USA

Description: Pyroxenes are mostly Ca-poor, but diopside or another Ca-rich pyroxene may be present in small quantities.

References:

Lonsdale, John T. (1927) The Florence Meteorite of Williamson County, Texas. American Mineralogist, 12 (11) 398-404

ⓘ Quartz

Formula: SiO₂

Localities:

Round Rock, Williamson County, Texas, USA
Lake Georgetown area, Georgetown, Williamson County, Texas, USA

ⓘ Quartz var. Chalcedony

Formula: SiO₂

Locality: Lake Georgetown area, Georgetown, Williamson County, Texas, USA

References:

Bill Morgenstern - Collection

ⓘ 'Serpentine Subgroup'

Formula: D₃[Si₂O₅](OH)₄

References:

Girard, Roselle M. (1964, February) Texas Rocks and Minerals - An Amateur's Guide. Guidebook 6. University of Texas - Bureau of Economic Geology

ⓘ Taenite

Formula: (Ni,Fe)

Locality: Florence meteorite, Florence, Williamson County, Texas, USA

References:

Lonsdale, John T. (1927) The Florence Meteorite of Williamson County, Texas. American Mineralogist, 12 (11) 398-404

ⓘ Troilite

Formula: FeS

Locality: Florence meteorite, Florence, Williamson County, Texas, USA

References:

Lonsdale, John T. (1927) The Florence Meteorite of Williamson County, Texas. American Mineralogist, 12 (11) 398-404

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘ	Native Gold	1.AA.05	Au
ⓘ	Native Iron	1.AE.05	Fe
ⓘ	var. Kamacite	1.AE.05	(Fe,Ni)
ⓘ	Taenite	1.AE.10	(Ni,Fe)
Group 2 - Sulphides and Sulfosalts
ⓘ	Troilite	2.CC.10	FeS
ⓘ	Pyrite	2.EB.05a	FeS₂
ⓘ	Marcasite	2.EB.10a	FeS₂
Group 4 - Oxides and Hydroxides
ⓘ	Chromite	4.BB.05	Fe²⁺Cr³⁺₂O₄
ⓘ	Quartz var. Chalcedony	4.DA.05	SiO₂
ⓘ		4.DA.05	SiO₂
Group 5 - Nitrates and Carbonates
ⓘ	Calcite	5.AB.05	CaCO₃
ⓘ	Aragonite	5.AB.15	CaCO₃
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘ	Celestine	7.AD.35	SrSO₄
Unclassified
ⓘ	'Fayalite-Forsterite Series'	-
ⓘ	'Plagioclase'	-	(Na,Ca)[(Si,Al)AlSi₂]O₈
ⓘ	'Pyroxene Group'	-	ADSi₂O₆
ⓘ	'Orthopyroxene Subgroup'	-
ⓘ	'Serpentine Subgroup'	-	D₃[Si₂O₅](OH)₄

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Serpentine Subgroup	D₃[Si₂O₅](OH)₄
C	Carbon
C	ⓘ Aragonite	CaCO₃
C	ⓘ Calcite	CaCO₃
O	Oxygen
O	ⓘ Aragonite	CaCO₃
O	ⓘ Calcite	CaCO₃
O	ⓘ Celestine	SrSO₄
O	ⓘ Quartz var. Chalcedony	SiO₂
O	ⓘ Chromite	Fe²⁺Cr₂³⁺O₄
O	ⓘ Quartz	SiO₂
O	ⓘ Fayalite-Forsterite Series
O	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
O	ⓘ Pyroxene Group	ADSi₂O₆
O	ⓘ Serpentine Subgroup	D₃[Si₂O₅](OH)₄
Na	Sodium
Na	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
Mg	Magnesium
Mg	ⓘ Fayalite-Forsterite Series
Al	Aluminium
Al	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
Si	Silicon
Si	ⓘ Quartz var. Chalcedony	SiO₂
Si	ⓘ Quartz	SiO₂
Si	ⓘ Fayalite-Forsterite Series
Si	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
Si	ⓘ Pyroxene Group	ADSi₂O₆
Si	ⓘ Serpentine Subgroup	D₃[Si₂O₅](OH)₄
S	Sulfur
S	ⓘ Celestine	SrSO₄
S	ⓘ Marcasite	FeS₂
S	ⓘ Pyrite	FeS₂
S	ⓘ Troilite	FeS
Ca	Calcium
Ca	ⓘ Aragonite	CaCO₃
Ca	ⓘ Calcite	CaCO₃
Ca	ⓘ Plagioclase	(Na,Ca)[(Si,Al)AlSi₂]O₈
Cr	Chromium
Cr	ⓘ Chromite	Fe²⁺Cr₂³⁺O₄
Fe	Iron
Fe	ⓘ Chromite	Fe²⁺Cr₂³⁺O₄
Fe	ⓘ Native Iron	Fe
Fe	ⓘ Native Iron var. Kamacite	(Fe,Ni)
Fe	ⓘ Marcasite	FeS₂
Fe	ⓘ Pyrite	FeS₂
Fe	ⓘ Taenite	(Ni,Fe)
Fe	ⓘ Troilite	FeS
Fe	ⓘ Fayalite-Forsterite Series
Ni	Nickel
Ni	ⓘ Native Iron var. Kamacite	(Fe,Ni)
Ni	ⓘ Taenite	(Ni,Fe)
Sr	Strontium
Sr	ⓘ Celestine	SrSO₄
Au	Gold
Au	ⓘ Native Gold	Au

Fossils

There are 74 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

0.01 Ma (Pleistocene)

Oldest Fossil Listed

145 Ma (Late Jurassic)

Stratigraphic Units

Click here to view 14 stratigraphic units.

Fossils from Region

Click here to show the list.

Accepted Name	Hierarchy	Age
Anchura genus	Animalia : Mollusca : Gastropoda : Littorinimorpha : Aporrhaidae : *Anchura*	72.1 - 66 Ma Late/Upper Cretaceous
Turritella genus	Animalia : Mollusca : Gastropoda : Turritellidae : *Turritella*	66 - 59.2 Ma Paleocene
Cancellaria genus	Animalia : Mollusca : Gastropoda : Neogastropoda : Cancellariidae : *Cancellaria*	66 - 59.2 Ma Paleocene
Ringicula genus	Animalia : Mollusca : Gastropoda : Cephalaspidea : Ringiculidae : *Ringicula*	72.1 - 66 Ma Late/Upper Cretaceous
Tornatellaea genus	Animalia : Mollusca : Gastropoda : Cephalaspidea : Acteonidae : *Tornatellaea*	66 - 59.2 Ma Paleocene
Architectonica genus	Animalia : Mollusca : Gastropoda : Architectonicidae : *Architectonica*	66 - 59.2 Ma Paleocene
Ptycheulimella genus	Animalia : Mollusca : Gastropoda : Pyramidellidae : *Ptycheulimella*	66 - 59.2 Ma Paleocene
Cucullaea genus	Animalia : Mollusca : Bivalvia : Arcida : Cucullaeidae : *Cucullaea*	66 - 59.2 Ma Paleocene
Kelliella genus	Animalia : Mollusca : Bivalvia : Venerida : Kelliellidae : *Kelliella*	66 - 61.6 Ma Paleocene
Siliqua genus	Animalia : Mollusca : Bivalvia : Adapedonta : Pharidae : *Siliqua*	66 - 59.2 Ma Paleocene
Terebratulina genus	Animalia : Brachiopoda : Rhynchonellata : Terebratulida : Cancellothyrididae : *Terebratulina*	72.1 - 66 Ma Late/Upper Cretaceous
Theropoda unranked clade	Animalia : Chordata : Saurischia : Theropoda	113 - 100.5 Ma Early/Lower Cretaceous
Myotis genus	Animalia : Chordata : Mammalia : Chiroptera : Vespertilionidae : *Myotis*	0.126 - 0.0117 Ma Pleistocene
Neotoma genus	Animalia : Chordata : Mammalia : Rodentia : Cricetidae : *Neotoma*	0.126 - 0.0117 Ma Pleistocene
Sylvilagus genus	Animalia : Chordata : Mammalia : Lagomorpha : Leporidae : *Sylvilagus*	0.126 - 0.0117 Ma Pleistocene
Camelops genus	Animalia : Chordata : Mammalia : Artiodactyla : Camelidae : *Camelops*	0.126 - 0.0117 Ma Pleistocene
Proboscidea order	Animalia : Chordata : Mammalia : Proboscidea	0.126 - 0.0117 Ma Pleistocene
Cynomys ludovicianus species	Animalia : Chordata : Mammalia : Rodentia : Sciuridae : Cynomys : *Cynomys ludovicianus*	0.126 - 0.0117 Ma Pleistocene
Canis dirus species	Animalia : Chordata : Mammalia : Carnivora : Canidae : Canis : *Canis dirus*	0.126 - 0.0117 Ma Pleistocene
Canis latrans species	Animalia : Chordata : Mammalia : Carnivora : Canidae : Canis : *Canis latrans*	0.126 - 0.0117 Ma Pleistocene
Panthera onca species	Animalia : Chordata : Mammalia : Carnivora : Felidae : Panthera : *Panthera onca*	0.126 - 0.0117 Ma Pleistocene
Lynx rufus species	Animalia : Chordata : Mammalia : Carnivora : Felidae : Lynx : *Lynx rufus*	0.126 - 0.0117 Ma Pleistocene
Platygonus compressus species	Animalia : Chordata : Mammalia : Artiodactyla : Tayassuidae : Platygonus : *Platygonus compressus*	0.126 - 0.0117 Ma Pleistocene
Grallatoridae family	Animalia : Chordata : Saurischia : Grallatoridae	113 - 100.5 Ma Early/Lower Cretaceous
Brontopodus birdi species	Animalia : Chordata : Saurischia : Brontopodus : *Brontopodus birdi*	113 - 100.5 Ma Early/Lower Cretaceous
Corbula (Caryocorbula) subgenus	Animalia : Mollusca : Bivalvia : Pholadida : Corbulidae : Corbula : *Corbula (Caryocorbula)*	66 - 59.2 Ma Paleocene
Venericardia (Baluchicardia) bulla species	Animalia : Mollusca : Bivalvia : Carditida : Carditidae : Baluchicardia : *Venericardia (Baluchicardia) bulla*	66 - 59.2 Ma Paleocene
Agaronia genus	Animalia : Mollusca : Gastropoda : Neogastropoda : Olivellidae : *Agaronia*	66 - 59.2 Ma Paleocene
Ledina smirna species	Animalia : Mollusca : Bivalvia : Nuculanida : Nuculanidae : Ledina : *Ledina smirna*	66 - 59.2 Ma Paleocene
Stoliczkaia (Lamnayella) scotti species	Animalia : Mollusca : Cephalopoda : Ammonitida : Lyelliceratidae : Stoliczkaiella : *Stoliczkaia (Lamnayella) scotti*	99.6 - 93.5 Ma Late/Upper Cretaceous
Drepanochilus genus	Animalia : Mollusca : Gastropoda : Littorinimorpha : Aporrhaidae : *Drepanochilus*	72.1 - 66 Ma Late/Upper Cretaceous
Wadeopsammia nodosa species	Animalia : Cnidaria : Anthozoa : Scleractinia : Dendrophylliidae : Wadeopsammia : *Wadeopsammia nodosa*	72.1 - 66 Ma Late/Upper Cretaceous
Caryophyllia konincki species	Animalia : Cnidaria : Anthozoa : Scleractinia : Caryophylliidae : Caryophyllia : *Caryophyllia konincki*	72.1 - 66 Ma Late/Upper Cretaceous
Caryophyllia mediavia species	Animalia : Cnidaria : Anthozoa : Scleractinia : Caryophylliidae : Caryophyllia : *Caryophyllia mediavia*	66 - 61.6 Ma Paleocene
Micrabacia radiata species	Animalia : Cnidaria : Anthozoa : Scleractinia : Micrabaciidae : Micrabacia : *Micrabacia radiata*	83.6 - 72.1 Ma Late/Upper Cretaceous
Flabellum conoideum species	Animalia : Cnidaria : Anthozoa : Scleractinia : Flabellidae : Flabellum : *Flabellum conoideum*	66 - 59.2 Ma Paleocene
Neophlycticeras (Neophlycticeras) texanum species	Animalia : Mollusca : Cephalopoda : Ammonitida : Lyelliceratidae : Neophlycticeras : *Neophlycticeras (Neophlycticeras) texanum*	99.6 - 93.5 Ma Late/Upper Cretaceous
Stoliczkaia (Faraudiella) roemeri species	Animalia : Mollusca : Cephalopoda : Ammonitida : Lyelliceratidae : Neophlycticeras : *Stoliczkaia (Faraudiella) roemeri*	99.6 - 93.5 Ma Late/Upper Cretaceous
Stoliczkaia (Faraudiella) archerae species	Animalia : Mollusca : Cephalopoda : Ammonitida : Lyelliceratidae : Neophlycticeras : *Stoliczkaia (Faraudiella) archerae*	99.6 - 93.5 Ma Late/Upper Cretaceous
Budaiceras hyatti species	Animalia : Mollusca : Cephalopoda : Ammonitida : Lyelliceratidae : Budaiceras : *Budaiceras hyatti*	99.6 - 93.5 Ma Late/Upper Cretaceous
Budaiceras elegantior species	Animalia : Mollusca : Cephalopoda : Ammonitida : Lyelliceratidae : Budaiceras : *Budaiceras elegantior*	99.6 - 93.5 Ma Late/Upper Cretaceous
Actinastrea guadalupae species	Animalia : Cnidaria : Anthozoa : Scleractinia : Actinastreidae : Actinastrea : *Actinastrea guadalupae*	109 - 105.3 Ma Early/Lower Cretaceous
Thamnasteria hoffmeisteri species	Animalia : Cnidaria : Anthozoa : Scleractinia : Thamnasteriidae : Thamnasteria : *Thamnasteria hoffmeisteri*	100.5 - 93.9 Ma Late/Upper Cretaceous
Trochocyathus coloradoensis species	Animalia : Cnidaria : Anthozoa : Scleractinia : Caryophylliidae : Trochocyathus : *Trochocyathus coloradoensis*	66 - 59.2 Ma Paleocene
Caryophyllia constricta species	Animalia : Cnidaria : Anthozoa : Scleractinia : Caryophylliidae : Caryophyllia : *Caryophyllia constricta*	66 - 59.2 Ma Paleocene
Palaeastacus walkeri species	Animalia : Arthropoda : Malacostraca : Decapoda : Erymidae : Palaeastacus : *Palaeastacus walkeri*	145 - 100.5 Ma Early/Lower Cretaceous
Placotrochus texanus species	Animalia : Cnidaria : Anthozoa : Scleractinia : Flabellidae : Placotrochus : *Placotrochus texanus*	100.5 - 93.9 Ma Late/Upper Cretaceous
Axosmilia craginiana species	Animalia : Cnidaria : Anthozoa : Scleractinia : Axosmiliidae : Axosmilia : *Axosmilia craginiana*	109 - 105.3 Ma Early/Lower Cretaceous
Pleurosmilia saxifisi species	Animalia : Cnidaria : Anthozoa : Scleractinia : Amphiastraeidae : Pleurosmilia : *Pleurosmilia saxifisi*	100.5 - 93.9 Ma Late/Upper Cretaceous
Budaia travisensis species	Animalia : Cnidaria : Anthozoa : Scleractinia : Amphiastraeidae : Budaia : *Budaia travisensis*	100.5 - 93.9 Ma Late/Upper Cretaceous
Stephanomorpha saxirotundi species	Animalia : Cnidaria : Anthozoa : Scleractinia : Siderastreidae : Stephanomorpha : *Stephanomorpha saxirotundi*	100.5 - 93.9 Ma Late/Upper Cretaceous
Epistreptophyllum budaensis species	Animalia : Cnidaria : Anthozoa : Scleractinia : Dermosmiliidae : Epistreptophyllum : *Epistreptophyllum budaensis*	100.5 - 93.9 Ma Late/Upper Cretaceous
Epistreptophyllum boesei species	Animalia : Cnidaria : Anthozoa : Scleractinia : Dermosmiliidae : Epistreptophyllum : *Epistreptophyllum boesei*	109 - 105.3 Ma Early/Lower Cretaceous
Epistreptophyllum shumardi species	Animalia : Cnidaria : Anthozoa : Scleractinia : Dermosmiliidae : Epistreptophyllum : *Epistreptophyllum shumardi*	109 - 105.3 Ma Early/Lower Cretaceous
Areopsammia bakerae species	Animalia : Cnidaria : Anthozoa : Scleractinia : Dendrophylliidae : Areopsammia : *Areopsammia bakerae*	100.5 - 93.9 Ma Late/Upper Cretaceous
Dimorpharaea manchacaensis species	Animalia : Cnidaria : Anthozoa : Scleractinia : Microsolenidae : Dimorpharaea : *Dimorpharaea manchacaensis*	100.5 - 93.9 Ma Late/Upper Cretaceous
Palaega williamsonensis species	Animalia : Arthropoda : Malacostraca : Isopoda : Cirolanidae : Palaega : *Palaega williamsonensis*	100.5 - 66 Ma Late/Upper Cretaceous
Goniopygus zitteli species	Animalia : Echinodermata : Echinoidea : Arbacioida : Acropeltidae : Goniopygus : *Goniopygus zitteli*	109 - 105.3 Ma Early/Lower Cretaceous
Diplopodia taffi species	Animalia : Echinodermata : Echinoidea : Pseudodiadematidae : Diplopodia : *Diplopodia taffi*	145 - 66 Ma Cretaceous

Fossil Localities

Click to show 19 fossil localities

Other Databases

Wikipedia:	https://en.wikipedia.org/wiki/Williamson_County,_Texas
Wikidata ID:	Q112686
GeoNames ID:	4742143

Localities in this Region

USA

Texas
- Williamson County
  - ⭔Florence
    - Florence meteorite
  - ⭔Georgetown

USA

Texas
- Williamson County
  - Georgetown
    - Leander Road Quarry
    - South Fork San Gabriel River occurrence
  - ⭔Hutto
    - Carmel Creek occurrence
  - ⭔Leander
  - ⭔Round Rock
  - Superior Stone Quarry
  - Texas Crushed Stone Quarries

Other Regions, Features and Areas that Intersect

North AmericaContinent

North America PlateTectonic Plate

Fort Worth BasinBasin
Granite-Rhyolite ProvinceMagmatic Province
Shawnee DomainDomain

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Williamson County, Texas, USAiRegional Level TypesWilliamson CountyCounty TexasState USACountry function showexplain() { $("#locexplain").toggle(); if (typeof movemap === "function") movemap(); }

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List of minerals arranged by Strunz 10th Edition classification

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Williamson County, Texas, USA i
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