Metamorphic Minerals

• Actinolite
• Alurgite
• Andalusite
• Andalusite (chiastolite)
• Antigorite
• Anthophyllite-Gedrite
• Biotite
• Brucite
• Calcite
• Cassiterite
• Charoite
• Chlorite
• Chloritoid
• Chrysocolla
• Cordierite
• Corundum
• Corundum (ruby)
• Kyanite
• Kornerupine
• Kyanite (reticite)
• Deerite
• Dumortierite
• Epidotes
Allanite
Pistacite
Piemontite
Zoisite

• Fassaite
• Fluorite
• Glaucophane
• Garnet
• Hercynite
• Hedenbergite
• Hydrogrossular
• Howieite
• Humites
• Jadeite
• Lawsonite
• Lazulite
• Lazurite
• Malachite
• Minnesotaite
• Muscovite
• Olivine
• Omphacite
• Omphacite Cr
• Pargasite
• Piemontite (Praborna)
• Pyrite
• Prehnite
• Pumpellyite
• Quartz
• Rhodonite
• Rutile
• Sapphirine
• Scapolite
• Serpentine
• Sillimanite
• Sillimanite (fibrolite)
• Staurolite
• Stilpnomelane
• Sugilite
• Talc
• Taramellite
• Thulite
• Tinaksite
• Tinzenite
• Titanite
• Tremolite
• Tourmaline
• Vesuvianite
• Violan
• Wollastonite
• Yoderite
• Zussmanite

Texture and Microstructure

• Augen
• Book shelf sliding
• Boudinage
• Corona
• Decussate
• Deformation lamellae
• Deformation twins
• Crenulation cleavage
• Fringes
• Granoblastic
• Kelyphite
• Kink Bands
• Lepidoblastic
• Mesh
• Mica fish
• Mylonitic
• Nematoblastic
• Oblique foliations
• Polygonal
• Porphyroblastic
• Porphyroclastic
• Pseudomorph
• Ribbon
• S-C fabric
• Skeletal garnet
• Symplectite
• Veins

Metamorphic Rocks

• Albite greenshist
• Amphibolite (felsic)
• Amphibolite (mafic)
• Amphibolite (mylonitic)
• Amphibolite with epidote
• Andalusite schist
• Anyolite
• Augen gneiss
• Blueschist
• Blueschist (Ile de Groix)
• Blueschist (retrograde)
• Buchite
• Calc-schists
• Carbonated peridotite
• Cataclasite
• Charoitite
• Chlorite schist
• Chloritoid Schist (Ile de Groix)
• Cordierite slate
• Corundum-fuchsite rock
• Deformed oolite
• Dunite (mylonitic)
• Eclogite
• Eclogite Porto Ottiolu
• Epidosite
• Gabbro (mylonitic)
• Garnet micaschist
• Glaucophane granofels
• Granite (mylonitic)
• Granulite (felsic)
• Granulite (mafic)
• Granulite (retrograde)
• Granulite (sapphirine-bearing)
• Greenschist
• Hornfels
• Hornfels (albite-epidote)
• Hornfels (cordierite, plagioclase)
• Hornfels (corundum, plagioclase)
• Hornfels (hydrogarnet)
• Jadeite metagranite
• Jadeitite
• Kinzigite
• Lapis lazuli
• Marble
• Marble (calc-silicate)
• Marble (diopside)
• Marble (forsterite)
• Marble (mylonitic)
• Marble (tremolite)
• Mylonite
• Ocean jasper
• Ophicalcite
• Peridotite (mylonitic)
• Phyllite
• Prasinite
• Pseudotachylyte
• Pseudotachylyte (Ivrea-Verbano)
• Quartzite
• Quartzite (tourmaline)
• Rhyolite (mylonitic)
• Rodingite
• Schist
• Seafloor basalt
• Serpentinite
• Serpentinized lherzolite
• Skarn
• Skiddaw Metamorphic Aureole
Skiddaw
1) Spotted slate
2) Andalusite slate
3) Cordierite slate

• Slate
• Slate (ottrelite)
• Talc schist
• Tourmalinite
• Ultramylonite (granitic)
• Ultramylonite (mafic)

Pargasite - NaCa₂(Fe₄²⁺Al)Si₆Al₂O₂₂(OH)₂

Named in 1814 by Count Fabian Gotthard von Steinheil for the locality in the Pargas Valley, Finland. Pargasite is a complex inosilicate mineral of the amphibole group. It occurs in high temperature regional metamorphic rocks and in the skarns within contact aureoles around igneous intrusions. Pargasite is the main water-storage site in the uppermost mantle, however it becomes unstable at depths greater than 90 km. This has significant consequences for the water storage capacity, and the solidus temperature of the lherzolite of the upper mantle.

Optical properties:

• Form: Prismatic crystals.
• Color: Green to greenish blue.
• Interference colors: II-III order.

Bibliography

• Bucher, K., & Grapes, R. (2011). Petrogenesis of metamorphic rocks. Springer Science & Business Media.
• Fossen, H. (2016). Structural geology. Cambridge University Press.
• Howie, R. A., Zussman, J., & Deer, W. (1992). An introduction to the rock-forming minerals (p. 696). Longman.
• Passchier, Cees W., Trouw, Rudolph A. J: Microtectonics (2005).
• Philpotts, A., & Ague, J. (2009). Principles of igneous and metamorphic petrology. Cambridge University Press.
• Shelley, D. (1993). Igneous and metamorphic rocks under the microscope: classification, textures, microstructures and mineral preferred-orientations.
• Vernon, R. H. & Clarke, G. L. (2008): Principles of Metamorphic Petrology. Cambridge University Press.
• Vernon, R. H. (2018). A practical guide to rock microstructure. Cambridge university press.

Photo

Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)
Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)
Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)
Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 10x (Field of view = 2mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)
Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 10x (Field of view = 2mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 10x (Field of view = 2mm)
Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)
Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)	Pargasite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)
Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)
Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)
Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)
Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)
Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 2x (Field of view = 7mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). XPL image, 2x (Field of view = 7mm)
Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)
Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)	Pargasite and magnetite crystals in a skarn from Sassi Neri mine, Elba (Italy). PPL image, 10x (Field of view = 2mm)