Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Eldora-Union area, Hardin County, Iowa, USAi
Regional Level Types
Eldora-Union areaArea
Hardin CountyCounty
IowaState
USACountry

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Latitude & Longitude (WGS84):
42° North , 93° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~29km
GRN:
N29W50
Type:
Area
Köppen climate type:
Dfa : Hot-summer humid continental climate
Mindat Locality ID:
44645
Long-form identifier:
mindat:1:2:44645:4
GUID (UUID V4):
0


In geodes

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


3 valid minerals.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz
var. Chalcedony		4.DA.05SiO2
ⓘ4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘGypsum7.CD.40CaSO4 · 2H2O

List of minerals for each chemical element

HHydrogen
Hⓘ GypsumCaSO4 · 2H2O
CCarbon
Cⓘ CalciteCaCO3
OOxygen
Oⓘ CalciteCaCO3
Oⓘ Quartz var. ChalcedonySiO2
Oⓘ GypsumCaSO4 · 2H2O
Oⓘ QuartzSiO2
SiSilicon
Siⓘ Quartz var. ChalcedonySiO2
Siⓘ QuartzSiO2
SSulfur
Sⓘ GypsumCaSO4 · 2H2O
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ GypsumCaSO4 · 2H2O

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate
USA

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