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Cactus Jack pegmatite, Burnet County, Texas, USAi
Regional Level Types
Cactus Jack pegmatitePegmatite
Burnet CountyCounty
TexasState
USACountry

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PhotosMapsSearch
03376270017272060428846.jpg
Aquamarine

Cactus Jack pegmatite, Burnet County, Texas, USA
07307690017272256813743.jpg
Monazite-(Ce)

Cactus Jack pegmatite, Burnet County, Texas, USA
07263050017272060541018.jpg
Euxenite-(Y), etc.

Cactus Jack pegmatite, Burnet County, Texas, USA
02815100017272256824050.jpg
Aquamarine

Cactus Jack pegmatite, Burnet County, Texas, USA
07307690017272256813743.jpg
Monazite-(Ce)

Cactus Jack pegmatite, Burnet County, Texas, USA
04459060017272256826169.jpg
Euxenite-(Y), etc.

Cactus Jack pegmatite, Burnet County, Texas, USA
03376270017272060428846.jpg
Aquamarine

Cactus Jack pegmatite, Burnet County, Texas, USA
09087700017272256824768.jpg
Monazite-(Ce)

Cactus Jack pegmatite, Burnet County, Texas, USA
Latitude & Longitude (WGS84):
30° North , 98° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~41km
GRN:
N21W60
Type:
Pegmatite
Köppen climate type:
Cfa : Humid subtropical climate
Mindat Locality ID:
132154
Long-form identifier:
mindat:1:2:132154:1
GUID (UUID V4):
0


Named by Franklin Roberts, co-developer of this location, in honor of "Cactus" Jack Carson, also a co-developer. Jack was the owner-operator of Cactus Canyon Quarries, Inc and was something of a local Texas legend since the 1950s. He and his son Andy Carson were instrumental in helping Mr. Roberts with the initial excavation of the new pegmatite. Without their heavy equipment and experience, he'd still be out in a sweltering Texas cow pasture trying to dig a hole in solid rock with nothing but a pick and shovel. Cactus Jack passed away within a year of excavating the pegmatite.

5 miles east of Lake Buchanan.

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


22 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

Detailed Mineral List:

ⓘ Albite
Formula: Na(AlSi3O8)
✪ Beryl
Formula: Be3Al2(Si6O18)
Habit: Hexagonal
Colour: green, blue-green
Fluorescence: none
Description: Tapered hexagonal crystal segments up to 12 cm between opposite faces. Some specimens found growing from milky quartz matrix. Deeper material may be of gem guality.
✪ Beryl var. Aquamarine
Formula: Be3Al2Si6O18
Habit: Hexagonal
Colour: green, blue-green
Fluorescence: none
Description: Tapered hexagonal crystal segments up to 12 cm between opposite faces. Some specimens found growing from milky quartz matrix. Deeper material may be of gem guality.
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Habit: Hexagonal books to 2 cm in thickness, 10 cm in girth.
Colour: Black, Golden (when weathered)
Fluorescence: None
Description: Occurs in the graphic granite zone of the pegmatite. Tiny cyrtolite zircons sometimes found between biotite laminae.
ⓘ Euxenite-(Y)
Formula: (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
ⓘ Fluorite
Formula: CaF2
References:
Franklin Roberts
ⓘ Fluorite var. Chlorophane
Formula: CaF2
References:
Franklin Roberts
ⓘ Galena
Formula: PbS
Habit: Massive, fracture-filling
Colour: Dark gray
Fluorescence: None
Description: Occurs as radiogenic galena in the interstitial spaces of radioactive rare-earth minerals from orange clay-filled crystal pockets in the pegmatite.
ⓘ Ilmenite
Formula: Fe2+TiO3
ⓘ 'Ixiolite-(Mn2+)-Ixiolite-(Fe2+) Series'
ⓘ Microcline
Formula: K(AlSi3O8)
ⓘ 'Microlite Group'
Formula: A2-mTa2X6-wZ-n
✪ Monazite-(Ce)
Formula: Ce(PO4)
Habit: Tabular, Monoclinic, Masses to 2.4 kg
Colour: Brick-red, Brown, Tan
Fluorescence: None
Description: Exceptionally large, euhedral crystals with pronounced radioactivity. Polished section microprobe analysis indicates a high degree of homogeneity. Th content is 8-16 weight percent.
References:
F Roberts, 2006
✪ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Habit: Tetragonal, tapering foliated columnar, curved faces
Colour: Metallic silver with black mottling
Fluorescence: None
Description: Occurs as tapered columns of curved tetragonal flakes to 3cm length, 1-2cm girth. This variety is also known as "ball-peen" mica due to its resemblance to decorative hammered metal.
References:
F Roberts, 2006
ⓘ Opal
Formula: SiO2 · nH2O
ⓘ Opal var. Opal-AN
Formula: SiO2 · nH2O
ⓘ Quartz
Formula: SiO2
References:
F Roberts, 2006
ⓘ Quartz var. Milky Quartz
Formula: SiO2
Description: Forms the central dike of the pegmatite. Large crystal pockets occur in this dike that are lined with euhedral water-clear quartz crystals and possibly beryl.
ⓘ Quartz var. Smoky Quartz
Formula: SiO2
References:
F Roberts, 2006
ⓘ Rutile
Formula: TiO2
ⓘ Samarskite-(Y)
Formula: YFe3+Nb2O8
ⓘ Spessartine
Formula: Mn2+3Al2(SiO4)3
ⓘ Tanteuxenite-(Y)
Formula: Y(Ta,Nb,Ti)2(O,OH)6
Habit: metamict
Fluorescence: none
Description: Occurs in mixed-phase rare-earth mineral nodules from orange clay-filled pockets at quartz-microcline contacts.
ⓘ Thorianite
Formula: ThO2
ⓘ Thorite
Formula: Th(SiO4)
References:
F Roberts, 2006
ⓘ Uraninite
Formula: UO2
ⓘ Uranophane
Formula: Ca(UO2)2(SiO3OH)2 · 5H2O
ⓘ Uranopolycrase
Formula: (U4+,Y)(Ti,Nb)2O6
Habit: metamict
Fluorescence: none
Description: Occurs in mixed-phase rare-earth mineral nodules from orange clay-filled pockets at quartz-microcline contacts.
ⓘ 'Wad'
Habit: Earthy
Colour: brown, black, bluish-black
Fluorescence: none
Description: Normally found as thick weathered alteration coatings on euhedral spessartine garnets in the graphic granite zone of the pegmatite.
✪ Xenotime-(Yb)
Formula: Yb(PO4)
Habit: Massive, Tetragonal Bipyramidal
Colour: gray, black
Fluorescence: None
Description: Found as radioactive 1-3 cm nodules and 3-10 mm crystals at quartz-blocky microcline contacts and in orange clay-filled pockets near these zones.
ⓘ Zircon
Formula: Zr(SiO4)

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘGalena2.CD.10PbS
Group 3 - Halides
ⓘFluorite
var. Chlorophane		3.AB.25CaF2
ⓘ3.AB.25CaF2
Group 4 - Oxides and Hydroxides
ⓘ'Ixiolite-(Mn2+)-Ixiolite-(Fe2+) Series'4..
ⓘ'Microlite Group'4.00.A2-mTa2X6-wZ-n
ⓘIlmenite4.CB.05Fe2+TiO3
ⓘQuartz4.DA.05SiO2
ⓘvar. Smoky Quartz4.DA.05SiO2
ⓘvar. Milky Quartz4.DA.05SiO2
ⓘOpal
var. Opal-AN		4.DA.10SiO2 · nH2O
ⓘ4.DA.10SiO2 · nH2O
ⓘRutile4.DB.05TiO2
ⓘSamarskite-(Y)4.DB.25YFe3+Nb2O8
ⓘEuxenite-(Y)4.DG.05(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
ⓘTanteuxenite-(Y)4.DG.05Y(Ta,Nb,Ti)2(O,OH)6
ⓘUranopolycrase4.DG.05(U4+,Y)(Ti,Nb)2O6
ⓘThorianite4.DL.05ThO2
ⓘUraninite4.DL.05UO2
Group 8 - Phosphates, Arsenates and Vanadates
ⓘXenotime-(Yb)8.AD.35Yb(PO4)
ⓘMonazite-(Ce)8.AD.50Ce(PO4)
Group 9 - Silicates
ⓘSpessartine9.AD.25Mn2+3Al2(SiO4)3
ⓘThorite9.AD.30Th(SiO4)
ⓘZircon9.AD.30Zr(SiO4)
ⓘUranophane9.AK.15Ca(UO2)2(SiO3OH)2 · 5H2O
ⓘBeryl
var. Aquamarine		9.CJ.05Be3Al2Si6O18
ⓘ9.CJ.05Be3Al2(Si6O18)
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘMicrocline9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)
Unclassified
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Wad'-

List of minerals for each chemical element

HHydrogen
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ Opal var. Opal-ANSiO2 · nH2O
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ OpalSiO2 · nH2O
Hⓘ Tanteuxenite-(Y)Y(Ta,Nb,Ti)2(O,OH)6
Hⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
BeBeryllium
Beⓘ Beryl var. AquamarineBe3Al2Si6O18
Beⓘ BerylBe3Al2(Si6O18)
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ Beryl var. AquamarineBe3Al2Si6O18
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ BerylBe3Al2(Si6O18)
Oⓘ Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Oⓘ Opal var. Opal-ANSiO2 · nH2O
Oⓘ IlmeniteFe2+TiO3
Oⓘ Ixiolite-(Mn2+)-Ixiolite-(Fe2+) Series
Oⓘ MicroclineK(AlSi3O8)
Oⓘ Monazite-(Ce)Ce(PO4)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ OpalSiO2 · nH2O
Oⓘ QuartzSiO2
Oⓘ RutileTiO2
Oⓘ Samarskite-(Y)YFe3+Nb2O8
Oⓘ Quartz var. Smoky QuartzSiO2
Oⓘ SpessartineMn32+Al2(SiO4)3
Oⓘ Tanteuxenite-(Y)Y(Ta,Nb,Ti)2(O,OH)6
Oⓘ ThorianiteThO2
Oⓘ ThoriteTh(SiO4)
Oⓘ UraniniteUO2
Oⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Oⓘ Uranopolycrase(U4+,Y)(Ti,Nb)2O6
Oⓘ ZirconZr(SiO4)
Oⓘ Quartz var. Milky QuartzSiO2
Oⓘ Xenotime-(Yb)Yb(PO4)
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fⓘ Fluorite var. ChlorophaneCaF2
Fⓘ FluoriteCaF2
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ Beryl var. AquamarineBe3Al2Si6O18
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ BerylBe3Al2(Si6O18)
Alⓘ MicroclineK(AlSi3O8)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ SpessartineMn32+Al2(SiO4)3
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ Beryl var. AquamarineBe3Al2Si6O18
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ BerylBe3Al2(Si6O18)
Siⓘ Opal var. Opal-ANSiO2 · nH2O
Siⓘ MicroclineK(AlSi3O8)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ OpalSiO2 · nH2O
Siⓘ QuartzSiO2
Siⓘ Quartz var. Smoky QuartzSiO2
Siⓘ SpessartineMn32+Al2(SiO4)3
Siⓘ ThoriteTh(SiO4)
Siⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Siⓘ ZirconZr(SiO4)
Siⓘ Quartz var. Milky QuartzSiO2
PPhosphorus
Pⓘ Monazite-(Ce)Ce(PO4)
Pⓘ Xenotime-(Yb)Yb(PO4)
SSulfur
Sⓘ GalenaPbS
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ MicroclineK(AlSi3O8)
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ Fluorite var. ChlorophaneCaF2
Caⓘ Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Caⓘ FluoriteCaF2
Caⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Tiⓘ IlmeniteFe2+TiO3
Tiⓘ RutileTiO2
Tiⓘ Tanteuxenite-(Y)Y(Ta,Nb,Ti)2(O,OH)6
Tiⓘ Uranopolycrase(U4+,Y)(Ti,Nb)2O6
MnManganese
Mnⓘ Ixiolite-(Mn2+)-Ixiolite-(Fe2+) Series
Mnⓘ SpessartineMn32+Al2(SiO4)3
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ IlmeniteFe2+TiO3
Feⓘ Ixiolite-(Mn2+)-Ixiolite-(Fe2+) Series
Feⓘ Samarskite-(Y)YFe3+Nb2O8
YYttrium
Yⓘ Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Yⓘ Samarskite-(Y)YFe3+Nb2O8
Yⓘ Tanteuxenite-(Y)Y(Ta,Nb,Ti)2(O,OH)6
Yⓘ Uranopolycrase(U4+,Y)(Ti,Nb)2O6
ZrZirconium
Zrⓘ ZirconZr(SiO4)
NbNiobium
Nbⓘ Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Nbⓘ Samarskite-(Y)YFe3+Nb2O8
Nbⓘ Tanteuxenite-(Y)Y(Ta,Nb,Ti)2(O,OH)6
Nbⓘ Uranopolycrase(U4+,Y)(Ti,Nb)2O6
CeCerium
Ceⓘ Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Ceⓘ Monazite-(Ce)Ce(PO4)
YbYtterbium
Ybⓘ Xenotime-(Yb)Yb(PO4)
TaTantalum
Taⓘ Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Taⓘ Ixiolite-(Mn2+)-Ixiolite-(Fe2+) Series
Taⓘ Microlite GroupA2-mTa2X6-wZ-n
Taⓘ Tanteuxenite-(Y)Y(Ta,Nb,Ti)2(O,OH)6
PbLead
Pbⓘ GalenaPbS
ThThorium
Thⓘ Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Thⓘ ThorianiteThO2
Thⓘ ThoriteTh(SiO4)
UUranium
Uⓘ Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Uⓘ UraniniteUO2
Uⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Uⓘ Uranopolycrase(U4+,Y)(Ti,Nb)2O6

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

Franklin Roberts postings.
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