Plagioclase Mineral Gallery

Plagioclase: (Na,Ca)(Si,Al)4O8  
Albite: NaAlSi3O8

Comments: Colorless, lustrous blocky albite crystals to 3 cm in size with a thick dusting of micaceous green micro chlorite.
Location: Acushnet Quarry, Bristol Co., Massachussetts, USA. Scale: 17 x 15 x 7.5 cm matrix.
© Dan Weinrich

Plagioclase: (Na,Ca)(Si,Al)4O8  
Albite: NaAlSi3O8

Comments: Crystal group of bladed albite (variety cleavelandite) crystals.
Location: Taquaral, Minas Gerais, Brazil. Scale: 7.4 x 5 cm.
© John Veevaert

Plagioclase: (Na,Ca)(Si,Al)4O8  
Labradorite: (Ca,Na)(Si,Al)4O8

Comments: Dual view of a cleavage fragment of labradorite showing the multi-colored labradorescence (schiller effect) and the same area viewed without the color. The color is due to optical interference on Bøggild exsolution lamellae.
Location: Ihosy, Betroka district, Toliara Province, Madagascar. Scale: Picture size 3x3 cm.
© Dave Barthelmy

Plagioclase: (Na,Ca)(Si,Al)4O8  
Oligoclase: (Na,Ca)(Si,Al)4O8

Comments: Rectangular cleavage fragment of salmon-orange oligoclase (sunstone) feldspar.
Location: Norway. Scale: 47x30x7 mm.
© John Betts - Fine Minerals

Plagioclase: (Na,Ca)(Si,Al)4O8  
Anorthite: CaAl2Si2O8

Comments: Opaque white crystal of anorthite with dark brown solidified lava coating.
Location: Miyake-jima, Shizuoka, Japan. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Plagioclase: (Na,Ca)(Si,Al)4O8  
Andesine: (Na,Ca)(Si,Al)4O8

Comments: Translucent andesine crystal twin.
Location: Maeyama Ueda shi, Nagano, Japan. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Plagioclase: (Na,Ca)(Si,Al)4O8  
Bytownite: (Ca,Na)(Si,Al)4O8

Comments: Translucent crystalline bytownite.
Location: Crystal Bay, Hennepin County, Minnesota, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Plagioclase: (Na,Ca)(Si,Al)4O8  
Oligoclase: (Na,Ca)(Si,Al)4O8

Comments: Clear glassy crystalline oligoclase with milky quartz and muscovite.
Location: Bakersville, Mitchell County, North Carolina, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Plagioclase: (Na,Ca)(Si,Al)4O8

Comments: Plagioclase, variety kenyite, crystals in volcanic rock.
Location: Kirinyaga (Mount Kenya), Central Province, Kenya. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Plagioclase: (Na,Ca)(Si,Al)4O8  
Albite: NaAlSi3O8

Comments: Colorless, lustrous blocky albite crystals to 3 cm in size with a thick dusting of micaceous green micro chlorite.
Location: Acushnet Quarry, Bristol Co., Massachussetts, USA. Scale: 17 x 15 x 7.5 cm matrix.
© Dan Weinrich

Plagioclase: (Na,Ca)(Si,Al)4O8  
Albite: NaAlSi3O8

Comments: Crystal group of bladed albite (variety cleavelandite) crystals.
Location: Taquaral, Minas Gerais, Brazil. Scale: 7.4 x 5 cm.
© John Veevaert

Plagioclase: (Na,Ca)(Si,Al)4O8  
Labradorite: (Ca,Na)(Si,Al)4O8

Comments: Dual view of a cleavage fragment of labradorite showing the multi-colored labradorescence (schiller effect) and the same area viewed without the color. The color is due to optical interference on Bøggild exsolution lamellae.
Location: Ihosy, Betroka district, Toliara Province, Madagascar. Scale: Picture size 3x3 cm.
© Dave Barthelmy

Plagioclase: (Na,Ca)(Si,Al)4O8  
Oligoclase: (Na,Ca)(Si,Al)4O8

Comments: Rectangular cleavage fragment of salmon-orange oligoclase (sunstone) feldspar.
Location: Norway. Scale: 47x30x7 mm.
© John Betts - Fine Minerals

Plagioclase: (Na,Ca)(Si,Al)4O8  
Anorthite: CaAl2Si2O8

Comments: Opaque white crystal of anorthite with dark brown solidified lava coating.
Location: Miyake-jima, Shizuoka, Japan. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Plagioclase: (Na,Ca)(Si,Al)4O8  
Andesine: (Na,Ca)(Si,Al)4O8

Comments: Translucent andesine crystal twin.
Location: Maeyama Ueda shi, Nagano, Japan. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Plagioclase: (Na,Ca)(Si,Al)4O8  
Bytownite: (Ca,Na)(Si,Al)4O8

Comments: Translucent crystalline bytownite.
Location: Crystal Bay, Hennepin County, Minnesota, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Plagioclase: (Na,Ca)(Si,Al)4O8  
Oligoclase: (Na,Ca)(Si,Al)4O8

Comments: Clear glassy crystalline oligoclase with milky quartz and muscovite.
Location: Bakersville, Mitchell County, North Carolina, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Plagioclase: (Na,Ca)(Si,Al)4O8

Comments: Plagioclase, variety kenyite, crystals in volcanic rock.
Location: Kirinyaga (Mount Kenya), Central Province, Kenya. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species