Group 2 - Sulphides and Sulfosalts
ⓘ	Sphalerite	2.CB.05a	ZnS
ⓘ	Pyrite	2.EB.05a	FeS₂
ⓘ	Marcasite	2.EB.10a	FeS₂
Group 4 - Oxides and Hydroxides
ⓘ	Goethite	4.00.	Fe³⁺O(OH)
Group 5 - Nitrates and Carbonates
ⓘ	Calcite	5.AB.05	CaCO₃
ⓘ	Siderite	5.AB.05	FeCO₃
ⓘ	Dolomite	5.AB.10	CaMg(CO₃)₂
ⓘ	var. Iron-bearing Dolomite	5.AB.10	Ca(Mg,Fe)(CO₃)₂
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘ	Baryte	7.AD.35	BaSO₄
ⓘ	Halotrichite	7.CB.85	Fe²⁺Al₂(SO₄)₄ · 22H₂O
ⓘ	Gypsum	7.CD.40	CaSO₄ · 2H₂O
ⓘ	var. Selenite	7.CD.40	CaSO₄ · 2H₂O
Unclassified
ⓘ	'Petrified Wood'	-

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Goethite	Fe³⁺O(OH)
H	ⓘ Gypsum	CaSO₄ · 2H₂O
H	ⓘ Halotrichite	Fe²⁺Al₂(SO₄)₄ · 22H₂O
H	ⓘ Gypsum var. Selenite	CaSO₄ · 2H₂O
C	Carbon
C	ⓘ Calcite	CaCO₃
C	ⓘ Dolomite	CaMg(CO₃)₂
C	ⓘ Siderite	FeCO₃
C	ⓘ Dolomite var. Iron-bearing Dolomite	Ca(Mg,Fe)(CO₃)₂
O	Oxygen
O	ⓘ Baryte	BaSO₄
O	ⓘ Calcite	CaCO₃
O	ⓘ Dolomite	CaMg(CO₃)₂
O	ⓘ Goethite	Fe³⁺O(OH)
O	ⓘ Gypsum	CaSO₄ · 2H₂O
O	ⓘ Halotrichite	Fe²⁺Al₂(SO₄)₄ · 22H₂O
O	ⓘ Siderite	FeCO₃
O	ⓘ Gypsum var. Selenite	CaSO₄ · 2H₂O
O	ⓘ Dolomite var. Iron-bearing Dolomite	Ca(Mg,Fe)(CO₃)₂
Mg	Magnesium
Mg	ⓘ Dolomite	CaMg(CO₃)₂
Mg	ⓘ Dolomite var. Iron-bearing Dolomite	Ca(Mg,Fe)(CO₃)₂
Al	Aluminium
Al	ⓘ Halotrichite	Fe²⁺Al₂(SO₄)₄ · 22H₂O
S	Sulfur
S	ⓘ Baryte	BaSO₄
S	ⓘ Gypsum	CaSO₄ · 2H₂O
S	ⓘ Halotrichite	Fe²⁺Al₂(SO₄)₄ · 22H₂O
S	ⓘ Marcasite	FeS₂
S	ⓘ Pyrite	FeS₂
S	ⓘ Sphalerite	ZnS
S	ⓘ Gypsum var. Selenite	CaSO₄ · 2H₂O
Ca	Calcium
Ca	ⓘ Calcite	CaCO₃
Ca	ⓘ Dolomite	CaMg(CO₃)₂
Ca	ⓘ Gypsum	CaSO₄ · 2H₂O
Ca	ⓘ Gypsum var. Selenite	CaSO₄ · 2H₂O
Ca	ⓘ Dolomite var. Iron-bearing Dolomite	Ca(Mg,Fe)(CO₃)₂
Fe	Iron
Fe	ⓘ Goethite	Fe³⁺O(OH)
Fe	ⓘ Halotrichite	Fe²⁺Al₂(SO₄)₄ · 22H₂O
Fe	ⓘ Marcasite	FeS₂
Fe	ⓘ Pyrite	FeS₂
Fe	ⓘ Siderite	FeCO₃
Fe	ⓘ Dolomite var. Iron-bearing Dolomite	Ca(Mg,Fe)(CO₃)₂
Zn	Zinc
Zn	ⓘ Sphalerite	ZnS
Ba	Barium
Ba	ⓘ Baryte	BaSO₄

Fossils

There are 4 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

299 Ma (Permian)

Oldest Fossil Listed

359 Ma (Late/Upper Devonian)

Stratigraphic Units

Unit	No. Occurrences	Age
Pella	1	336 - 318.1 Ma (Carboniferous)

Fossils from Region

Click here to show the list.

Accepted Name	Hierarchy	Age
Pentremites genus	Animalia : Echinodermata : Pentremitidae : *Pentremites*	345 - 318.1 Ma Carboniferous

Fossil Localities

Click to show 2 fossil localities

USA

Iowa
- Mahaska County
  - Paleozoic🐚 Mich Mine Coal Balls
  - Carboniferous🐚 Pentremites Blastoids

Other Databases

Wikipedia:	https://en.wikipedia.org/wiki/Mahaska_County,_Iowa
Wikidata ID:	Q485922
GeoNames ID:	4865894

Localities in this Region

Other Regions, Features and Areas that Intersect

North AmericaContinent

North America PlateTectonic Plate

Great Plains DomainDomain
Yavapai TerraneVolcanic Arc

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.

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Detailed Mineral List:

Gallery:

List of minerals arranged by Strunz 10th Edition classification

List of minerals for each chemical element

Fossils

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Localities in this Region

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Mahaska County, Iowa, USA i
Regional Level Types
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