Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
  
Hornfels is a metamorphic rock formed by the contact between mudstone or other clay rich rock, and a hot igneous body, and represents a heat altered equivalent of the original rock
  
History
  
  
Origin
USA
  
New Zealand
  
Discoverer
Unknown
  
Unknown
  
Etymology
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
  
From German which means hornstone
  
Class
Metamorphic Rocks
  
Metamorphic 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
  
Granular, Platy
  
Color
Black, Brown, Colourless, Green, Grey, Pink, White
  
Brown, Dark Greenish - Grey, Green, Reddish Brown
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
No
  
Stain Resistant
No
  
No
  
Wind Resistant
Yes
  
No
  
Acid Resistant
Yes
  
No
  
Appearance
Dull and Soft
  
Dull
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
  
Decorative Aggregates, Flooring, Homes, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
  
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
  
for Road Aggregate, Roadstone
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments
  
Artifacts, Monuments
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Gemstone
  
Cemetery Markers, Commemorative Tablets, Creating Artwork
  
Types
Not Available
  
Biotite hornfels
  
Features
Host Rock for Lead
  
Smooth to touch
  
Archaeological Significance
  
  
Monuments
Used
  
Used
  
Famous Monuments
Data Not Available
  
Data Not Available
  
Sculpture
Not Yet Used
  
Not Yet Used
  
Famous Sculptures
Not Applicable
  
Not Applicable
  
Pictographs
Not Used
  
Used
  
Petroglyphs
Not Used
  
Used
  
Figurines
Not Yet Used
  
Not Yet Used
  
Fossils
Absent
  
Absent
  
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.
  
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Hornfels is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
  
Composition
  
  
Mineral Content
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
  
Andalusite
  
Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
  
Fe, Mg
  
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, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
7
  
2-3
  
Grain Size
Very fine-grained
  
Fine Grained
  
Fracture
Uneven
  
Conchoidal
  
Streak
Light to dark brown
  
Unknown
  
Porosity
Less Porous
  
Highly Porous
  
Luster
Vitreous
  
Shiny
  
Compressive Strength
60.00 N/mm2
  
25
Cleavage
Irregular
  
Perfect
  
Toughness
Not Available
  
Not Yet Found
  
Specific Gravity
2.46-2.86
  
3.4-3.9
  
Transparency
Transparent to Translucent
  
Opaque
  
Density
2.7-2.9 g/cm3
  
0.25-0.30 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
0.84 kJ/Kg K
  
15
Resistance
Heat Resistant
  
Heat Resistant, Impact Resistant, Pressure Resistant
  
Deposits in Eastern Continents
  
  
Asia
South Korea
  
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand
  
Africa
Western Africa
  
Cameroon, East Africa, Tanzania, Western Africa
  
Europe
Great Britain, Switzerland
  
United Kingdom
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Not Yet Found
  
Canada, USA
  
South America
Not Yet Found
  
Bolivia, Brazil, Colombia, Ecuador
  
Deposits in Oceania Continent
  
  
Australia
Central Australia, Western Australia
  
New South Wales, New Zealand, Queensland, Western Australia
  
Pseudotachylite vs Hornfels 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 Hornfels characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Pseudotachylite and Properties of Hornfels. Learn more about Pseudotachylite vs Hornfels in the next section. The interior uses of Pseudotachylite include Decorative aggregates, Entryways and Interior decoration whereas the interior uses of Hornfels include Decorative aggregates, Flooring, Homes and Interior decoration. Due to some exceptional properties of Pseudotachylite and Hornfels, 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 Hornfels include For road aggregate, Roadstone.
More about Pseudotachylite and Hornfels
Here you can know more about Pseudotachylite and Hornfels. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Pseudotachylite and Hornfels consists of mineral content and compound content. The mineral content of Pseudotachylite includes Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides and mineral content of Hornfels includes Andalusite. You can also check out the list of all Metamorphic Rocks. When we have to compare Pseudotachylite vs Hornfels, 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, Hornfels is available in brown, dark greenish - grey, green, reddish brown colors. Appearance of Pseudotachylite is Dull and Soft and that of Hornfels is Dull. Properties of rock is another aspect for Pseudotachylite vs Hornfels. The hardness of Pseudotachylite is 7 and that of Hornfels is 2-3. The types of Pseudotachylite are Not Available whereas types of Hornfels are Biotite hornfels. 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 Hornfels is unknown. The specific heat capacity of Pseudotachylite is 0.92 kJ/Kg K and that of Hornfels is 0.84 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 Hornfels is heat resistant, impact resistant, pressure resistant.