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Twin Knobs No. 1 Mine, Murfreesboro, Pike County, Arkansas, USAi
Regional Level Types
Twin Knobs No. 1 MineMine
Murfreesboro- not defined -
Pike CountyCounty
ArkansasState
USACountry

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PhotosMapsSearch
08806730017272010392759.jpg
Former Site 1

Twin Knobs No. 1 Mine, Murfreesboro, Pike County, Arkansas, USA
01641710017272010414250.jpg
Twin Knobs 2

Twin Knobs No. 1 Mine, Murfreesboro, Pike County, Arkansas, USA
05162920017272010424469.jpg
Twin Knobs 3

Twin Knobs No. 1 Mine, Murfreesboro, Pike County, Arkansas, USA
08806730017272010392759.jpg
Former Site 1

Twin Knobs No. 1 Mine, Murfreesboro, Pike County, Arkansas, USA
01641710017272010414250.jpg
Twin Knobs 2

Twin Knobs No. 1 Mine, Murfreesboro, Pike County, Arkansas, USA
05162920017272010424469.jpg
Twin Knobs 3

Twin Knobs No. 1 Mine, Murfreesboro, Pike County, Arkansas, USA
08806730017272010392759.jpg
Former Site 1

Twin Knobs No. 1 Mine, Murfreesboro, Pike County, Arkansas, USA
01641710017272010414250.jpg
Twin Knobs 2

Twin Knobs No. 1 Mine, Murfreesboro, Pike County, Arkansas, USA
Latitude & Longitude (WGS84):
34° 0' 0'' North , 93° 41' 59'' West
Latitude & Longitude (decimal):
34.00000,-93.70000
GRN:
N23W56
Type:
Mine
Köppen climate type:
Cfa : Humid subtropical climate
Nearest Settlements:
PlacePopulationDistance
Murfreesboro1,580 (2017)7.0km
Nashville4,479 (2017)14.8km
Blevins308 (2017)18.2km
Delight268 (2017)18.5km
Mineral Springs1,161 (2017)24.1km
Mindat Locality ID:
25536
Long-form identifier:
mindat:1:2:25536:6
GUID (UUID V4):
0


A diamond property consisting of 13 acres.

Located 2 miles SW of the Crater of Diamonds.

Mineralization is in a lamproite diatreme.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


18 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:

ⓘ Almandine
Formula: Fe2+3Al2(SiO4)3
ⓘ Baryte
Formula: BaSO4
ⓘ Calcite
Formula: CaCO3
ⓘ Chromite
Formula: Fe2+Cr3+2O4
ⓘ 'Clinopyroxene Subgroup'
ⓘ Diamond
Formula: C
ⓘ Diopside
Formula: CaMgSi2O6
ⓘ Enstatite
Formula: Mg2Si2O6
ⓘ 'Fayalite-Forsterite Series'
ⓘ 'Feldspar Group'
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
ⓘ Ilmenite
Formula: Fe2+TiO3
ⓘ Ilmenite var. Picroilmenite
Formula: (Fe2+,Mg)TiO3
ⓘ 'Leucoxene'
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Illite
Formula: K0.65Al2.0[Al0.65Si3.35O10](OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ 'Olivine Group'
Formula: M2SiO4
ⓘ 'Orthopyroxene Subgroup'
ⓘ Perovskite
Formula: CaTiO3
ⓘ Phlogopite
Formula: KMg3(AlSi3O10)(OH)2
ⓘ 'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
ⓘ 'Potassium richterite'
ⓘ Priderite
Formula: K(Ti4+7Fe3+)O16
ⓘ Pyrope
Formula: Mg3Al2(SiO4)3
ⓘ Pyrope var. Chromium-bearing Pyrope
Formula: Mg3(Al,Cr)2(SiO4)3
ⓘ 'Pyroxene Group'
Formula: ADSi2O6
ⓘ Quartz
Formula: SiO2
ⓘ Rutile
Formula: TiO2
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4
ⓘ Spinel
Formula: MgAl2O4
ⓘ Talc
Formula: Mg3Si4O10(OH)2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘDiamond1.CB.10aC
Group 4 - Oxides and Hydroxides
ⓘChromite4.BB.05Fe2+Cr3+2O4
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘSpinel4.BB.05MgAl2O4
ⓘIlmenite4.CB.05Fe2+TiO3
ⓘvar. Picroilmenite4.CB.05(Fe2+,Mg)TiO3
ⓘPerovskite4.CC.30CaTiO3
ⓘQuartz4.DA.05SiO2
ⓘRutile4.DB.05TiO2
ⓘPriderite4.DK.05bK(Ti4+7Fe3+)O16
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘBaryte7.AD.35BaSO4
Group 9 - Silicates
ⓘAlmandine9.AD.25Fe2+3Al2(SiO4)3
ⓘPyrope9.AD.25Mg3Al2(SiO4)3
ⓘvar. Chromium-bearing Pyrope9.AD.25Mg3(Al,Cr)2(SiO4)3
ⓘEnstatite9.DA.05Mg2Si2O6
ⓘDiopside9.DA.15CaMgSi2O6
ⓘTalc9.EC.05Mg3Si4O10(OH)2
ⓘMuscovite
var. Illite		9.EC.15K0.65Al2.0[Al0.65Si3.35O10](OH)2
ⓘ9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘPhlogopite9.EC.20KMg3(AlSi3O10)(OH)2
Unclassified
ⓘ'Feldspar Group'-
ⓘ'Leucoxene'-
ⓘ'Clinopyroxene Subgroup'-
ⓘ'Fayalite-Forsterite Series'-
ⓘ'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8
ⓘ'Pyroxene Group'-ADSi2O6
ⓘ'Garnet Group'-X3Z2(SiO4)3
ⓘ'Orthopyroxene Subgroup'-
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4
ⓘ'Olivine Group'-M2SiO4
ⓘ'Potassium richterite'-

List of minerals for each chemical element

HHydrogen
Hⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Hⓘ TalcMg3Si4O10(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
CCarbon
Cⓘ CalciteCaCO3
Cⓘ DiamondC
OOxygen
Oⓘ AlmandineFe32+Al2(SiO4)3
Oⓘ BaryteBaSO4
Oⓘ CalciteCaCO3
Oⓘ ChromiteFe2+Cr23+O4
Oⓘ DiopsideCaMgSi2O6
Oⓘ EnstatiteMg2Si2O6
Oⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Oⓘ IlmeniteFe2+TiO3
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ PerovskiteCaTiO3
Oⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Oⓘ PrideriteK(Ti74+Fe3+)O16
Oⓘ PyropeMg3Al2(SiO4)3
Oⓘ QuartzSiO2
Oⓘ RutileTiO2
Oⓘ SpinelMgAl2O4
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ Fayalite-Forsterite Series
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Oⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Oⓘ Pyroxene GroupADSi2O6
Oⓘ Garnet GroupX3Z2(SiO4)3
Oⓘ Ilmenite var. Picroilmenite(Fe2+,Mg)TiO3
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
Oⓘ Olivine GroupM2SiO4
Oⓘ Pyrope var. Chromium-bearing PyropeMg3(Al,Cr)2(SiO4)3
NaSodium
Naⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MgMagnesium
Mgⓘ DiopsideCaMgSi2O6
Mgⓘ EnstatiteMg2Si2O6
Mgⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Mgⓘ PyropeMg3Al2(SiO4)3
Mgⓘ SpinelMgAl2O4
Mgⓘ TalcMg3Si4O10(OH)2
Mgⓘ Fayalite-Forsterite Series
Mgⓘ Ilmenite var. Picroilmenite(Fe2+,Mg)TiO3
Mgⓘ Pyrope var. Chromium-bearing PyropeMg3(Al,Cr)2(SiO4)3
AlAluminium
Alⓘ AlmandineFe32+Al2(SiO4)3
Alⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Alⓘ PyropeMg3Al2(SiO4)3
Alⓘ SpinelMgAl2O4
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Alⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Alⓘ Pyrope var. Chromium-bearing PyropeMg3(Al,Cr)2(SiO4)3
SiSilicon
Siⓘ AlmandineFe32+Al2(SiO4)3
Siⓘ DiopsideCaMgSi2O6
Siⓘ EnstatiteMg2Si2O6
Siⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Siⓘ PyropeMg3Al2(SiO4)3
Siⓘ QuartzSiO2
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ Fayalite-Forsterite Series
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Siⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Siⓘ Pyroxene GroupADSi2O6
Siⓘ Garnet GroupX3Z2(SiO4)3
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
Siⓘ Olivine GroupM2SiO4
Siⓘ Pyrope var. Chromium-bearing PyropeMg3(Al,Cr)2(SiO4)3
SSulfur
Sⓘ BaryteBaSO4
KPotassium
Kⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Kⓘ PrideriteK(Ti74+Fe3+)O16
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ DiopsideCaMgSi2O6
Caⓘ PerovskiteCaTiO3
Caⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
TiTitanium
Tiⓘ IlmeniteFe2+TiO3
Tiⓘ PerovskiteCaTiO3
Tiⓘ PrideriteK(Ti74+Fe3+)O16
Tiⓘ RutileTiO2
Tiⓘ Ilmenite var. Picroilmenite(Fe2+,Mg)TiO3
CrChromium
Crⓘ ChromiteFe2+Cr23+O4
Crⓘ Pyrope var. Chromium-bearing PyropeMg3(Al,Cr)2(SiO4)3
FeIron
Feⓘ AlmandineFe32+Al2(SiO4)3
Feⓘ ChromiteFe2+Cr23+O4
Feⓘ IlmeniteFe2+TiO3
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PrideriteK(Ti74+Fe3+)O16
Feⓘ Fayalite-Forsterite Series
Feⓘ Ilmenite var. Picroilmenite(Fe2+,Mg)TiO3
BaBarium
Baⓘ BaryteBaSO4

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

Mullen & Murphy (1985).
Dummett, H. T. (1987). Geology and petrography of the Twin Knobs# 1 lamproite, Pike County, Arkansas. Mantle Metasomatism and Alkaline Magmatism, 215, 205.
Rocks & Minerals (1988) 63: 118.
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