Holohyaline texture

A term applied to igneous rocks that have a glassy texture. Holohyaline rocks were generally cooled rapidly, which inhibits growth rate and nucleation of crystals. A few tiny crystals, called microlites, may be present.

Bibliography



• Cox et al. (1979): The Interpretation of Igneous Rocks, George Allen and Unwin, London.
• Howie, R. A., Zussman, J., & Deer, W. (1992). An introduction to the rock-forming minerals (p. 696). Longman.
• Le Maitre, R. W., Streckeisen, A., Zanettin, B., Le Bas, M. J., Bonin, B., Bateman, P., & Lameyre, J. (2002). Igneous rocks. A classification and glossary of terms, 2. Cambridge University Press.
• Middlemost, E. A. (1986). Magmas and magmatic rocks: an introduction to igneous petrology.
• 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.


Photo
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Obsidian with magmatic foliation. PPL image , 2x (Field of view = 7mm)
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Volcanic glass showing perlitic texture (concentric curved fractures) in a Holohyaline rock. PPL image , 10x (Field of view = 2mm)
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Volcanic glass showing perlitic texture (concentric curved fractures) in a Holohyaline rock. PPL image , 10x (Field of view = 2mm)
osssidiana(5).jpg

Volcanic glass showing perlitic texture (concentric curved fractures) in a Holohyaline rock. PPL image , 10x (Field of view = 2mm)
osssidiana(6).jpg

Volcanic glass showing perlitic texture (concentric curved fractures) in a Holohyaline rock. PPL image , 10x (Field of view = 2mm)
osssidiana(7).jpg

Volcanic glass showing perlitic texture (concentric curved fractures) in a Holohyaline rock. PPL image , 10x (Field of view = 2mm)
osssidiana(8).jpg

Obsidian with magmatic foliation. PPL image , 2x (Field of view = 7mm)
osssidiana(9).jpg

Obsidian with magmatic foliation. PPL image , 2x (Field of view = 7mm)
osssidiana(10).jpg

Obsidian with magmatic foliation. XPL image , 2x (Field of view = 7mm)
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Obsidian with magmatic foliation. PPL image , 10x (Field of view = 2mm)
osssidiana(12).jpg

Obsidian with magmatic foliation. PPL image , 10x (Field of view = 2mm)
osssidiana(13).jpg

Obsidian with magmatic foliation. XPL image , 10x (Field of view = 2mm)
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Crystallites in a Obsidian. PPL image , 10x (Field of view = 1mm)
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Crystallites in a Obsidian. PPL image , 10x (Field of view = 1mm)
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Crystallites in a Obsidian. PPL image , 10x (Field of view = 1mm)
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Crystallites in a Obsidian. PPL image , 10x (Field of view = 1mm)