Fundamental Minerals

Sialic Minerals

Feldspar

Feldspathoid

Quartz

Femic Minerals

Accessory Minerals

Very Rare Minerals

Secondary Minerals

Texture

Alteration Products

Glass and related Texture

Volcanic Rocks

Komatiites

Lamprophyres

Alnöite

Alnöite: An ultramafic rock with phenocrysts of phlogopite-biotite, olivine and augite in a groundmass of melilite (often altered to calcite), augite and/or biotite with minor perovskite, garnet and calcite. Named after the type locality at Alnö Island, Västernorrland, Sweden. First description by Rosenbusch is dated in 1887.

Alnöites are mafic alkaline silicate rocks that belongs to the kimberlite family and are melilite-rich. The type locality (Stornäset or Näset ) from which alnöite was originally described and given the name "melilite basalt" by Törnebohm (1882), shows a black, dense rock with phenocrysts of gold-brown phlogopite and apatite.

alno2019(6).jpg

Gold-brown phlogopite crystals in a Alnoöite from Näset, Alnoö island. From Hildegard Wilske

Gold-brown phlogopite crystals in a Alnoöite from Näset, Alnoö island. From Hildegard Wilske

Bibliography

• Andersson, M. (2015). 3D Structure and Emplacement of the Alnö Alkaline and Carbonatite Complex, Sweden: Integrated Geophysical and Physical Property Investigations.
• Kresten P (1980): The Alnö complex: tectonics of dyke emplacement. Lithos 13:153–158.
• Brueckner H.K, Rex DC (1980): K-A and Rb-Sr geochronology and Sr isotopic study of the Alnö alkaline complex , northeastern Sweden. Lithos 13:111–119.

Photo
Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)	Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)	Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)
Phlogopite and apatite (I order gray) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. XPL image, 1x (Field of view = 9mm)	Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)	Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)
Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)	Phlogopite and apatite (I order gray) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. XPL image, 1x (Field of view = 9mm)	Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)
Phlogopite and apatite (I order gray) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. XPL image, 1x (Field of view = 9mm)	Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)	Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)
Phlogopite, altered olivine and apatite (I order gray) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. XPL image, 1x (Field of view = 9mm)	Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)	Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)
Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)	Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)	Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 1x (Field of view = 9mm)
Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)	Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)	Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)
Phlogopite (brown) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)	Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)	Phlogopite (brown) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)
Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)	Phlogopite and apatite (I order gray) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)	Phlogopite (brown) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)
Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)	Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)	Phlogopite (brown) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 2x (Field of view = 7mm)
Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 10x (Field of view = 2mm)	Phlogopite, altered olivine and apatite (I order gray) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. XPL image, 10x (Field of view = 2mm)	Altered olivine (yello-green) crystal in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 10x (Field of view = 2mm)
Phlogopite (brown), altered olivine (yello-green) and apatite (colorles) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 10x (Field of view = 2mm)	Phlogopite (brown), calcite (after melilite) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 10x (Field of view = 2mm)	Phlogopite, calcite (after melilite) crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. XPL image, 10x (Field of view = 2mm)
Phlogopite (brown), calcite (after melilite) and apatite crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 10x (Field of view = 2mm)	Phlogopite, calcite (after melilite) and apatite crystals in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 10x (Field of view = 2mm)	Phlogopite (brown) in a fine-grained groundmass. Alnöite, Alnö complex, Sweden. PPL image, 10x (Field of view = 2mm)