Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
Shoshonite is a basaltic rock, properly a potassic trachyandesite, composed of olivine, augite and plagioclase phenocrysts in a groundmass with calcic plagioclase and sanidine and some dark-colored volcanic glass
Discoverer
Unknown
Iddings
Etymology
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
From the place of origin called Shoshone riverin Wyoming
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Quench
Porphyritic
Color
Black, Brown, Green, Grey, Pink, White
Brown- Black, Dark Brown
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Dull
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
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Antiquity Uses
Artifacts, Monuments
Sculpture
Commercial Uses
Creating Artwork, Gemstone
Cemetery Markers, Creating Artwork
Types
Cataclastic rock
Intermediate volcanic rock
Features
Host Rock for Lead
Has High structural resistance against erosion and climate, Very fine grained rock
Archaeological Significance
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.
Shoshonite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Pyroxene
Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Aluminium Oxide, Iron(III) Oxide, Potassium Oxide, Sodium Oxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
-
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
-
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Very fine-grained
Medium to Fine Coarse Grained
Streak
Light to dark brown
White to Grey
Porosity
Less Porous
Less Porous
Specific Gravity
2.46-2.86
2.98
Transparency
Transparent to Translucent
Opaque
Density
2.7-2.9 g/cm3
2.9-3 g/cm3
Resistance
Heat Resistant
Heat Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
South Korea
India, Russia
Africa
Western Africa
South Africa
Europe
Great Britain, Switzerland
Iceland
Deposits in Western Continents
North America
-
Canada, USA
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
-
Pseudotachylite vs Shoshonite 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 Shoshonite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Pseudotachylite and Properties of Shoshonite. Learn more about Pseudotachylite vs Shoshonite in the next section. The interior uses of Pseudotachylite include Decorative aggregates, Entryways and Interior decoration whereas the interior uses of Shoshonite include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Pseudotachylite and Shoshonite, 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 Shoshonite include As dimension stone, Cobblestones, Rail track ballast, Roadstone.
More about Pseudotachylite and Shoshonite
Here you can know more about Pseudotachylite and Shoshonite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Pseudotachylite and Shoshonite consists of mineral content and compound content. The mineral content of Pseudotachylite includes Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides and mineral content of Shoshonite includes Pyroxene. You can also check out the list of all Metamorphic Rocks. When we have to compare Pseudotachylite vs Shoshonite, the texture, color and appearance plays an important role in determining the type of rock. Pseudotachylite is available in black, brown, green, grey, pink, white colors whereas, Shoshonite is available in brown- black, dark brown colors. Appearance of Pseudotachylite is Dull and Soft and that of Shoshonite is Dull. Properties of rock is another aspect for Pseudotachylite vs Shoshonite. The hardness of Pseudotachylite is 7 and that of Shoshonite is 6. The types of Pseudotachylite are Cataclastic rock whereas types of Shoshonite are Intermediate volcanic rock. 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 Shoshonite is white to grey. The specific heat capacity of Pseudotachylite is 0.92 kJ/Kg K and that of Shoshonite is 0.79 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 Shoshonite is heat resistant, pressure resistant.