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Phyllite and Pseudotachylite


Pseudotachylite and Phyllite


Definition

Definition
Phyllite is a fine-grained metamorphic rock with a well-developed laminar structure, and is intermediate between slate and schist rocks  
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.  

History
  
  

Origin
-  
USA  

Discoverer
Unknown  
Unknown  

Etymology
From Greek phullon leaf + -ite1  
From pseudo- +‎ tachylite, a glassy rock generated by frictional heat within faults.  

Class
Metamorphic Rocks  
Metamorphic Rocks  

Sub-Class
Durable Rock, Soft Rock  
Durable Rock, Hard Rock  

Family
  
  

Group
-  
-  

Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock  
Fine Grained Rock, Opaque Rock  

Texture

Texture
Phyllitic Sheen, Slaty  
Quench  

Color
Black to Grey, Light Greenish Grey  
Black, Brown, Green, Grey, Pink, White  

Maintenance
More  
Less  

Durability
Durable  
Durable  

Water Resistant
No  
Yes  

Scratch Resistant
No  
Yes  

Stain Resistant
No  
No  

Wind Resistant
No  
Yes  

Acid Resistant
No  
Yes  

Appearance
Crinkled or Wavy  
Dull and Soft  

Uses

Architecture
  
  

Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration  
Decorative Aggregates, Entryways, Interior Decoration  

Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration  
As Building Stone, As Facing Stone, Garden Decoration  

Other Architectural Uses
Curbing  
Curbing  

Industry
  
  

Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar, Roadstone  
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement  

Medical Industry
-  
-  

Antiquity Uses
Artifacts, Sculpture  
Artifacts, Monuments  

Other Uses
  
  

Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Writing Slates  
Creating Artwork, Gemstone  

Types

Types
Phyllite  
Cataclastic rock  

Features
Easily splits into thin plates, Is one of the oldest rock, Surfaces are often shiny  
Host Rock for Lead  

Archaeological Significance
  
  

Monuments
-  
-  

Famous Monuments
-  
-  

Sculpture
-  
-  

Famous Sculptures
-  
-  

Pictographs
-  
-  

Petroglyphs
-  
-  

Figurines
-  
-  

Fossils
Absent  
Absent  

Formation

Formation
Phyllite is a metamorphic rock which is formed by regional metamorphism of argillaceous sediments since their cleavage arose due to deviatoric stress.  
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Pseudotachylite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.  

Composition
  
  

Mineral Content
Albite, Alusite, Amphibole, Apatite, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc, Zircon  
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides  

Compound Content
CaO, Carbon Dioxide, MgO  
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur  

Transformation
  
  

Metamorphism
No  
Yes  

Types of Metamorphism
-  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism  

Weathering
Yes  
No  

Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering  
-  

Erosion
Yes  
No  

Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion  
-  

Properties

Physical Properties
  
  

Hardness
1-2  
7  

Grain Size
Medium to Fine Coarse Grained  
Very fine-grained  

Fracture
Conchoidal  
Uneven  

Streak
White  
Light to dark brown  

Porosity
Highly Porous  
Less Porous  

Luster
Phyllitic  
Vitreous  

Compressive Strength
50.00 N/mm2  
39
60.00 N/mm2  
37

Cleavage
Crenulation and Pervasive  
-  

Toughness
1.2  
-  

Specific Gravity
2.72-2.73  
2.46-2.86  

Transparency
Opaque  
Transparent to Translucent  

Density
2.18-3.3 g/cm3  
2.7-2.9 g/cm3  

Thermal Properties
  
  

Specific Heat Capacity
0.79 kJ/Kg K  
17
0.92 kJ/Kg K  
10

Resistance
Heat Resistant, Pressure Resistant, Water Resistant  
Heat Resistant  

Reserves

Deposits in Eastern Continents
  
  

Asia
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam  
South Korea  

Africa
Egypt, Ethiopia, Morocco, Nigeria, South Africa  
Western Africa  

Europe
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland  
Great Britain, Switzerland  

Others
-  
-  

Deposits in Western Continents
  
  

North America
Canada, Costa Rica, Cuba, Mexico, Panama, USA  
-  

South America
Brazil, Colombia, Guyana  
-  

Deposits in Oceania Continent
  
  

Australia
New South Wales, New Zealand, Queensland  
Central Australia, Western Australia  

Summary >>
<< Reserves

All about Phyllite and Pseudotachylite Properties

Know all about Phyllite and Pseudotachylite properties here. All properties of rocks are important as they define the type of rock and its application. Phyllite and Pseudotachylite belong to Metamorphic Rocks.Texture of Phyllite is Phyllitic Sheen, Slaty whereas that of Pseudotachylite is Quench. Phyllite appears Crinkled or Wavy and Pseudotachylite appears Dull and Soft. The luster of Phyllite is phyllitic while that of Pseudotachylite is vitreous. Phyllite is available in black to grey, light greenish grey colors whereas Pseudotachylite is available in black, brown, green, grey, pink, white colors. The commercial uses of Phyllite are cemetery markers, commemorative tablets, creating artwork, writing slates and that of Pseudotachylite are creating artwork, gemstone.

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