Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Opal from
Ioi mine, Kusatsu City, Shiga Prefecture, Japan


02021330017367504298298.jpg
Opal

Ioi mine, Kusatsu City, Shiga Prefecture, Japan
02021330017367504298298.jpg
Opal

Ioi mine, Kusatsu City, Shiga Prefecture, Japan
01194970017272724795095.jpg
Opal

Ioi mine, Kusatsu City, Shiga Prefecture, Japan
Locality type:Mine
Classification
Species:Opal
Formula:SiO2 · nH2O
Confirmation
Validity:Confirmed
Confirmation Methods:Visually Identified
Data
Mineral Data:Click here to view Opal data
Locality Data:Click here to view Ioi mine, Kusatsu City, Shiga Prefecture, Japan
Data Identifiers
Mindat Occurrence Record ID:874283
Long-form Identifier:1:3:874283:4
GUID (UUID V4):0
Nearest other occurrences of Opal
57.3km (35.6 miles) ⓘYamato Mine (Yamato-suigin Mine), Uda City, Nara Prefecture, Japan
References
Hiroaki Tano's collection
 
and/or  
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