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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Biotite from
Trachyte quarry, Ponzano, Bagnoregio, Viterbo Province, Lazio, Italy


Locality type:Quarry
Classification
Species:'Biotite' (not an IMA approved species)
Formula:K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Habit:tabular xls
Colour:brown
Abundance at site:Common
Confirmation
Validity:Confirmed
Confirmation Methods:Visually Identified, SEM-EDS
Associated Minerals:
Associates:Sanidine
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Trachyte quarry, Ponzano, Bagnoregio, Viterbo Province, Lazio, Italy
Data Identifiers
Mindat Occurrence Record ID:312253
Long-form Identifier:1:3:312253:2
GUID (UUID V4):0
Nearest other occurrences of Biotite
20.2km (12.5 miles) ⓘPoggio Pinzo (Gradoli pozzolana quarry), Gradoli, Viterbo Province, Lazio, Italy
20.9km (13.0 miles) ⓘMontenero Quarry, Onano, Viterbo Province, Lazio, Italy
27.5km (17.1 miles) ⓘSan Martino al Cimino, Viterbo, Viterbo Province, Lazio, Italy
28.5km (17.7 miles) ⓘCase Collina, Pitigliano, Grosseto Province, Tuscany, Italy
30.1km (18.7 miles) ⓘLe Carcarelle, Viterbo, Viterbo Province, Lazio, Italy
31.9km (19.8 miles) ⓘTre Croci, Vetralla, Viterbo Province, Lazio, Italy
51.1km (31.8 miles) ⓘSH2 deep well, Bracciano, Metropolitan City of Rome Capital, Lazio, Italy
51.7km (32.1 miles) ⓘMonte Rovello, Allumiere, Metropolitan City of Rome Capital, Lazio, Italy
53.6km (33.3 miles) ⓘSpizzicatore Hill, Allumiere, Metropolitan City of Rome Capital, Lazio, Italy
60.5km (37.6 miles) ⓘFosso Attici, Magliano Romano, Metropolitan City of Rome Capital, Lazio, Italy
References
C. Biagioni
 
and/or  
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