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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Muscovite from
Bryn-yr-Afr Mine, Ponterwyd, Trefeirig, Ceredigion, Wales, UK


Locality type:Mine
Classification
Species:Muscovite
Formula:KAl2(AlSi3O10)(OH)2
Comments:Off white crystal rossets to 1mm, commly staind yellow and red by Fe oxides.
Habit:Thin platy rossets
Quality for species:Poor for species, only of interest for locality collectors. (#)
Abundance at site:Rare
Confirmation
Validity:Confirmed
Confirmation Methods:Visually Identified
Data
Mineral Data:Click here to view Muscovite data
Locality Data:Click here to view Bryn-yr-Afr Mine, Ponterwyd, Trefeirig, Ceredigion, Wales, UK
Data Identifiers
Mindat Occurrence Record ID:39043
Long-form Identifier:1:3:39043:5
GUID (UUID V4):0
Nearest other occurrences of Muscovite
7.2km (4.5 miles) ⓘCastell Mine (Dyffryn Castell Mine; New Castell Mine; West Esgair Lle Mine; Gwaithddu Mine; Cripiau Bach Mine), Ponterwyd, Cwmrheidol, Ceredigion, Wales, UK
11.9km (7.4 miles) ⓘDyfngwm mine, Penegoes, Powys, Wales, UK
50.7km (31.5 miles) ⓘPrince Edward Mine (Moel Croesau), Trawsfynydd, Gwynedd, Wales, UK
57.7km (35.8 miles) ⓘDolyhir Quarry, Old Radnor, Powys, Wales, UK
59.4km (36.9 miles) ⓘLlechwedd slate quarry, Ffestiniog, Gwynedd, Wales, UK
73.8km (45.8 miles) ⓘLlandybie (Llandebie), Carmarthenshire, Wales, UK
84.6km (52.5 miles) ⓘCefn Coed Colliery, Crynant, Neath Port Talbot, Wales, UK
84.8km (52.7 miles) ⓘTal y Fan, Caerhun, Conwy, Wales, UK
References
S.Rust Collection
 
and/or  
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