Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
  
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
  
History
  
  
Origin
USA
  
Unknown
  
Discoverer
Unknown
  
Unknown
  
Etymology
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
  
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
  
Class
Metamorphic Rocks
  
Sedimentary Rocks
  
Sub-Class
Durable Rock, Hard Rock
  
Durable Rock, Medium Hardness Rock
  
Family
  
  
Group
Not Applicable
  
Not Applicable
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Quench
  
Clastic, Splintery
  
Color
Black, Brown, Colourless, Green, Grey, Pink, White
  
Black, Brown, Buff, Green, Grey, Red, Yellow
  
Maintenance
Less
  
More
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
No
  
Scratch Resistant
Yes
  
No
  
Stain Resistant
No
  
No
  
Wind Resistant
Yes
  
No
  
Acid Resistant
Yes
  
No
  
Appearance
Dull and Soft
  
Muddy
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
  
Decorative Aggregates, Homes, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
  
As Building Stone, As Facing Stone, Office Buildings
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
  
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments
  
Artifacts, Sculpture
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Gemstone
  
Creating Artwork, Pottery
  
Types
Not Available
  
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
  
Features
Host Rock for Lead
  
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
  
Archaeological Significance
  
  
Monuments
Used
  
Used
  
Famous Monuments
Data Not Available
  
Jantar Mantar in India
  
Sculpture
Not Yet Used
  
Used
  
Famous Sculptures
Not Applicable
  
Data Not Available
  
Pictographs
Not Used
  
Used
  
Petroglyphs
Not Used
  
Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Absent
  
Present
  
Formation
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.
  
Shale forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are later compacted hence forming shale.
  
Composition
  
  
Mineral Content
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
  
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
  
Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
  
Ca, Fe, Mg, Silicon Dioxide, Sodium
  
Transformation
  
  
Metamorphism
Yes
  
No
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
  
Not Applicable
  
Weathering
No
  
Yes
  
Types of Weathering
Not Applicable
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
No
  
Yes
  
Types of Erosion
Not Applicable
  
Chemical Erosion, Coastal Erosion, Glacier Erosion
  
Physical Properties
  
  
Hardness
7
  
3
  
Grain Size
Very fine-grained
  
Very fine-grained
  
Fracture
Uneven
  
Not Available
  
Streak
Light to dark brown
  
White
  
Porosity
Less Porous
  
Highly Porous
  
Luster
Vitreous
  
Dull
  
Compressive Strength
60.00 N/mm2
  
25
95.00 N/mm2
  
20
Cleavage
Irregular
  
Slaty
  
Toughness
Not Available
  
2.6
  
Specific Gravity
2.46-2.86
  
2.2-2.8
  
Transparency
Transparent to Translucent
  
Opaque
  
Density
2.7-2.9 g/cm3
  
2.4-2.8 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
0.39 kJ/Kg K
  
23
Resistance
Heat Resistant
  
Heat Resistant, Impact Resistant
  
Deposits in Eastern Continents
  
  
Asia
South Korea
  
Bangladesh, China, India, Russia
  
Africa
Western Africa
  
Ethiopia, Kenya, Morocco, South Africa, Tanzania
  
Europe
Great Britain, Switzerland
  
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Not Yet Found
  
USA
  
South America
Not Yet Found
  
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
  
Deposits in Oceania Continent
  
  
Australia
Central Australia, Western Australia
  
New South Wales, New Zealand, Queensland, Victoria, Western Australia
  
Pseudotachylite vs Shale Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Pseudotachylite vs Shale characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Pseudotachylite and Properties of Shale. Learn more about Pseudotachylite vs Shale in the next section. The interior uses of Pseudotachylite include Decorative aggregates, Entryways and Interior decoration whereas the interior uses of Shale include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Pseudotachylite and Shale, they have various applications in construction industry. The uses of Pseudotachylite in construction industry include As dimension stone, Cement manufacture, For road aggregate, Making natural cement and that of Shale include Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar.
More about Pseudotachylite and Shale
Here you can know more about Pseudotachylite and Shale. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Pseudotachylite and Shale consists of mineral content and compound content. The mineral content of Pseudotachylite includes Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides and mineral content of Shale includes Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides. You can also check out the list of all Metamorphic Rocks. When we have to compare Pseudotachylite vs Shale, the texture, color and appearance plays an important role in determining the type of rock. Pseudotachylite is available in black, brown, colourless, green, grey, pink, white colors whereas, Shale is available in black, brown, buff, green, grey, red, yellow colors. Appearance of Pseudotachylite is Dull and Soft and that of Shale is Muddy. Properties of rock is another aspect for Pseudotachylite vs Shale. The hardness of Pseudotachylite is 7 and that of Shale is 3. The types of Pseudotachylite are Not Available whereas types of Shale are Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Pseudotachylite is light to dark brown while that of Shale is white. The specific heat capacity of Pseudotachylite is 0.92 kJ/Kg K and that of Shale is 0.39 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Pseudotachylite is heat resistant whereas Shale is heat resistant, impact resistant.