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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Opal occurrence, Nioro du Sahel Cercle, Kayes Region, Malii
Regional Level Types
Opal occurrenceOccurrence
Nioro du Sahel CercleCercle
Kayes RegionRegion
MaliCountry

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PhotosMapsSearch
Latitude & Longitude:
15° North , 9° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~127km
GRN:
N11W07
Type:
Occurrence
Mindat Locality ID:
31090
Long-form identifier:
mindat:1:2:31090:0
GUID (UUID V4):
0


Locality with transparent bluish precious opal as well as yellow, green, and brown common opal.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


1 valid mineral.

Detailed Mineral List:

ⓘ Opal
Formula: SiO2 · nH2O

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘOpal4.DA.10SiO2 · nH2O

List of minerals for each chemical element

HHydrogen
Hⓘ OpalSiO2 · nH2O
OOxygen
Oⓘ OpalSiO2 · nH2O
SiSilicon
Siⓘ OpalSiO2 · nH2O

Other Regions, Features and Areas containing this locality

AfricaContinent
African PlateTectonic Plate
West AfricaUN Subregion

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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