Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
  
Argillites are highly compact sedimentary or slightly metamorphosed rocks that consist largely or wholly of particles of clay or silt but lack the fissility of shale or the cleavage characteristic of slate
  
History
  
  
Origin
USA
  
Unknown
  
Discoverer
Unknown
  
Unknown
  
Etymology
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
  
From Latin Argilla (clay) and -ite in English which became agrilla+ -ite = Argillite
  
Class
Metamorphic Rocks
  
Sedimentary Rocks
  
Sub-Class
Durable Rock, Hard Rock
  
Durable Rock, Soft Rock
  
Family
  
  
Group
Not Applicable
  
Not Applicable
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Quench
  
Clastic, Polished
  
Color
Black, Brown, Colourless, Green, Grey, Pink, White
  
Dark Grey to Black, Pink, Red, White
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
No
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
Yes
  
Yes
  
Acid Resistant
Yes
  
Yes
  
Appearance
Dull and Soft
  
Rough and Dull
  
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, Garden Decoration, Office Buildings
  
Other Architectural Uses
Curbing
  
Curbing, Whetstones
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
  
Used for flooring, stair treads, borders and window sills.
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments
  
Artifacts, Monuments, Sculpture
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Gemstone
  
Fire resistant, Used to manufracture paperweights and bookends
  
Types
Not Available
  
Not Available
  
Features
Host Rock for Lead
  
Is one of the oldest rock
  
Archaeological Significance
  
  
Monuments
Used
  
Used
  
Famous Monuments
Data Not Available
  
Data Not Available
  
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.
  
An argillite is a fine-grained sedimentary rock mainly composed of clay particles which forms from lithified muds which contain variable amounts of silt-sized particles.
  
Composition
  
  
Mineral Content
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
  
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
  
Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
  
Iron(III) Oxide, Potassium Oxide, MgO, Silicon Dioxide
  
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
  
Erosion
No
  
Yes
  
Types of Erosion
Not Applicable
  
Chemical Erosion
  
Physical Properties
  
  
Hardness
7
  
2-3
  
Grain Size
Very fine-grained
  
Fine Grained
  
Fracture
Uneven
  
Conchoidal to Uneven
  
Streak
Light to dark brown
  
White to Grey
  
Porosity
Less Porous
  
Highly Porous
  
Luster
Vitreous
  
Waxy and Dull
  
Compressive Strength
60.00 N/mm
2
  
25
Not Available
  
Cleavage
Irregular
  
Slaty
  
Toughness
Not Available
  
2.6
  
Specific Gravity
2.46-2.86
  
2.56-2.68
  
Transparency
Transparent to Translucent
  
Opaque
  
Density
2.7-2.9 g/cm3
  
2.54-2.66 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
0.87 kJ/Kg K
  
14
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 Argillite 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 Argillite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Pseudotachylite and Properties of Argillite. Learn more about Pseudotachylite vs Argillite in the next section. The interior uses of Pseudotachylite include Decorative aggregates, Entryways and Interior decoration whereas the interior uses of Argillite include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Pseudotachylite and Argillite, 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 Argillite include Used for flooring, stair treads, borders and window sills..
More about Pseudotachylite and Argillite
Here you can know more about Pseudotachylite and Argillite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Pseudotachylite and Argillite consists of mineral content and compound content. The mineral content of Pseudotachylite includes Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides and mineral content of Argillite includes Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz. You can also check out the list of all Metamorphic Rocks. When we have to compare Pseudotachylite vs Argillite, 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, Argillite is available in dark grey to black, pink, red, white colors. Appearance of Pseudotachylite is Dull and Soft and that of Argillite is Rough and Dull. Properties of rock is another aspect for Pseudotachylite vs Argillite. The hardness of Pseudotachylite is 7 and that of Argillite is 2-3. The types of Pseudotachylite are Not Available whereas types of Argillite are Not Available. 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 Argillite is white to grey. The specific heat capacity of Pseudotachylite is 0.92 kJ/Kg K and that of Argillite is 0.87 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 Argillite is heat resistant, impact resistant.