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Matlock drill core, Sioux County, Iowa, USAi
Regional Level Types
Matlock drill coreBorehole
Sioux CountyCounty
IowaState
USACountry

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Latitude & Longitude (WGS84):
43° 14' 37'' North , 95° 56' 6'' West
Latitude & Longitude (decimal):
43.24364,-95.93515
GeoHash:
G#: 9zey0bq0k
GRN:
N29W51
Type:
Borehole
Köppen climate type:
Dfa : Hot-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Boyden708 (2017)8.2km
Sheldon5,088 (2017)9.4km
George1,055 (2017)12.4km
Ashton430 (2017)13.9km
Hull2,244 (2017)17.2km
Mindat Locality ID:
31433
Long-form identifier:
mindat:1:2:31433:1
GUID (UUID V4):
0


Iowaite was found in a diamond drill core in serpentinite, at a depth of 1000-1500 feet. In late 1963, New Jersey Zinc drilled a series of exploration drill cores on an aeromagnetic anomaly in Sioux and Lyon counties in northwest Iowa. Later study of these cores revealed an altered Archean age layered mafic pluton that included a serpentinized zone with centimeter-thick chromite bands. Otter Creek layered igneous complex near the town of Matlock.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


19 valid minerals. 1 (TL) - type locality of 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:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ 'Amphibole Supergroup'
Formula: AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ Brucite
Formula: Mg(OH)2
ⓘ Calcite
Formula: CaCO3
ⓘ 'Chlorite Group'
ⓘ Chromite
Formula: Fe2+Cr3+2O4
ⓘ Chrysotile
Formula: Mg3(Si2O5)(OH)4
ⓘ Cummingtonite
Formula: ◻{Mg2}{Mg5}(Si8O22)(OH)2
ⓘ Dolomite
Formula: CaMg(CO3)2
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ Ferro-actinolite
Formula: ◻Ca2Fe2+5(Si8O22)(OH)2
ⓘ Grunerite
Formula: ◻{Fe2+2}{Fe2+5}(Si8O22)(OH)2
ⓘ Iowaite (TL)
Formula: Mg6Fe3+2(OH)16Cl2 · 4H2O
Type Locality:
ⓘ Magnesite
Formula: MgCO3
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Pyrite
Formula: FeS2
ⓘ Pyroaurite
Formula: Mg6Fe3+2(OH)16[CO3] · 4H2O
ⓘ Quartz
Formula: SiO2
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4
ⓘ Talc
Formula: Mg3Si4O10(OH)2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘChromite4.BB.05Fe2+Cr3+2O4
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘQuartz4.DA.05SiO2
ⓘBrucite4.FE.05Mg(OH)2
ⓘIowaite (TL)4.FL.05Mg6Fe3+2(OH)16Cl2 · 4H2O
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘMagnesite5.AB.05MgCO3
ⓘDolomite5.AB.10CaMg(CO3)2
ⓘPyroaurite5.DA.50Mg6Fe3+2(OH)16[CO3] · 4H2O
Group 9 - Silicates
ⓘChrysotile9.00.Mg3(Si2O5)(OH)4
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘCummingtonite9.DE.05◻{Mg2}{Mg5}(Si8O22)(OH)2
ⓘGrunerite9.DE.05◻{Fe2+2}{Fe2+5}(Si8O22)(OH)2
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘFerro-actinolite9.DE.10◻Ca2Fe2+5(Si8O22)(OH)2
ⓘTalc9.EC.05Mg3Si4O10(OH)2
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘAlbite9.FA.35Na(AlSi3O8)
Unclassified
ⓘ'Amphibole Supergroup'-AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ'Chlorite Group'-
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Hⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Hⓘ BruciteMg(OH)2
Hⓘ ChrysotileMg3(Si2O5)(OH)4
Hⓘ Cummingtonite◻{Mg2}{Mg5}(Si8O22)(OH)2
Hⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ Ferro-actinolite◻Ca2Fe52+(Si8O22)(OH)2
Hⓘ Grunerite◻{Fe22+}{Fe52+}(Si8O22)(OH)2
Hⓘ IowaiteMg6Fe23+(OH)16Cl2 · 4H2O
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ PyroauriteMg6Fe23+(OH)16[CO3] · 4H2O
Hⓘ TalcMg3Si4O10(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
CCarbon
Cⓘ CalciteCaCO3
Cⓘ DolomiteCaMg(CO3)2
Cⓘ MagnesiteMgCO3
Cⓘ PyroauriteMg6Fe23+(OH)16[CO3] · 4H2O
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Oⓘ BruciteMg(OH)2
Oⓘ CalciteCaCO3
Oⓘ ChrysotileMg3(Si2O5)(OH)4
Oⓘ ChromiteFe2+Cr23+O4
Oⓘ Cummingtonite◻{Mg2}{Mg5}(Si8O22)(OH)2
Oⓘ DolomiteCaMg(CO3)2
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ Ferro-actinolite◻Ca2Fe52+(Si8O22)(OH)2
Oⓘ Grunerite◻{Fe22+}{Fe52+}(Si8O22)(OH)2
Oⓘ IowaiteMg6Fe23+(OH)16Cl2 · 4H2O
Oⓘ MagnesiteMgCO3
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ PyroauriteMg6Fe23+(OH)16[CO3] · 4H2O
Oⓘ QuartzSiO2
Oⓘ TalcMg3Si4O10(OH)2
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
FFluorine
Fⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Mgⓘ BruciteMg(OH)2
Mgⓘ ChrysotileMg3(Si2O5)(OH)4
Mgⓘ Cummingtonite◻{Mg2}{Mg5}(Si8O22)(OH)2
Mgⓘ DolomiteCaMg(CO3)2
Mgⓘ IowaiteMg6Fe23+(OH)16Cl2 · 4H2O
Mgⓘ MagnesiteMgCO3
Mgⓘ PyroauriteMg6Fe23+(OH)16[CO3] · 4H2O
Mgⓘ TalcMg3Si4O10(OH)2
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Siⓘ ChrysotileMg3(Si2O5)(OH)4
Siⓘ Cummingtonite◻{Mg2}{Mg5}(Si8O22)(OH)2
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ Ferro-actinolite◻Ca2Fe52+(Si8O22)(OH)2
Siⓘ Grunerite◻{Fe22+}{Fe52+}(Si8O22)(OH)2
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ TalcMg3Si4O10(OH)2
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
SSulfur
Sⓘ PyriteFeS2
ClChlorine
Clⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Clⓘ IowaiteMg6Fe23+(OH)16Cl2 · 4H2O
KPotassium
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Caⓘ CalciteCaCO3
Caⓘ DolomiteCaMg(CO3)2
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Caⓘ Ferro-actinolite◻Ca2Fe52+(Si8O22)(OH)2
TiTitanium
Tiⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
CrChromium
Crⓘ ChromiteFe2+Cr23+O4
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Feⓘ ChromiteFe2+Cr23+O4
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ Ferro-actinolite◻Ca2Fe52+(Si8O22)(OH)2
Feⓘ Grunerite◻{Fe22+}{Fe52+}(Si8O22)(OH)2
Feⓘ IowaiteMg6Fe23+(OH)16Cl2 · 4H2O
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2
Feⓘ PyroauriteMg6Fe23+(OH)16[CO3] · 4H2O

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

Kohls, D. W., Rodda, J. L. (1967) Iowaite, a new hydrous magnesium hydroxide-ferric oxychloride from the Precambrian of Iowa. American Mineralogist, 52 (9-10) 1261-1271
Van Schmus, W. R., & Wallin, E. T. (1991). Studies of the Precambrian Geology of Iowa: Part 3. Geochronologic data for the Matlock drill holes. Journal of the Iowa Academy of Science: JIAS, 98(4), 182-188.
Windom, K. E., Seifert, K. E., & Anderson, R. R. (1991). Studies of the Precambrian geology of Iowa: Part 1. The Otter Creek layered igneous complex. Journal of the Iowa Academy of Science: JIAS, 98(4), 170-177.
Windom, K. E., Schmus, W. R. V., Seifert, K. E., Wallin, E. T., & Anderson, R. R. (1993). Archean and Proterozoic tectono-magmatic activity along the southern margin of the Superior Province in northwestern Iowa, United States. Canadian Journal of Earth Sciences, 30(6), 1275-1285.
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