Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
Discoverer
Van Tooren
Unknown
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Quench
Color
Black, Brown, Green, Grey, White
Black, Brown, Green, Grey, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Vesicular
Dull and Soft
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
Landscaping
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
Antiquity Uses
Artifacts, Sculpture
Artifacts, Monuments
Commercial Uses
Production of Lime, Soil Conditioner
Creating Artwork, Gemstone
Types
Igneous rock
Cataclastic rock
Features
Host Rock for Lead
Host Rock for Lead
Archaeological Significance
Formation
Tephrite 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.
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.
Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional 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, Sea Erosion, Water Erosion
-
Grain Size
Medium to Fine Coarse Grained
Very fine-grained
Streak
Bluish Black
Light to dark brown
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Vitreous
Cleavage
Crenulation and Pervasive
-
Specific Gravity
2.86
2.46-2.86
Transparency
Opaque
Transparent to Translucent
Density
2.8-2.9 g/cm3
2.7-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Africa
Namibia, Uganda
Western Africa
Europe
Germany, Hungary, Italy, Portugal, Spain
Great Britain, Switzerland
Deposits in Western Continents
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
Central Australia, Western Australia
Tephrite vs Pseudotachylite 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. Tephrite vs Pseudotachylite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Tephrite and Properties of Pseudotachylite. Learn more about Tephrite vs Pseudotachylite in the next section. The interior uses of Tephrite include Decorative aggregates, Flooring, Homes and Interior decoration whereas the interior uses of Pseudotachylite include Decorative aggregates, Entryways and Interior decoration. Due to some exceptional properties of Tephrite and Pseudotachylite, they have various applications in construction industry. The uses of Tephrite in construction industry include Landscaping and that of Pseudotachylite include As dimension stone, Cement manufacture, For road aggregate, Making natural cement.
More about Tephrite and Pseudotachylite
Here you can know more about Tephrite and Pseudotachylite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Tephrite and Pseudotachylite consists of mineral content and compound content. The mineral content of Tephrite includes Alkali feldspar, Nepheline, Plagioclase, Pyroxene and mineral content of Pseudotachylite includes Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides. You can also check out the list of all Igneous Rocks. When we have to compare Tephrite vs Pseudotachylite, the texture, color and appearance plays an important role in determining the type of rock. Tephrite is available in black, brown, green, grey, white colors whereas, Pseudotachylite is available in black, brown, green, grey, pink, white colors. Appearance of Tephrite is Vesicular and that of Pseudotachylite is Dull and Soft. Properties of rock is another aspect for Tephrite vs Pseudotachylite. The hardness of Tephrite is 6.5 and that of Pseudotachylite is 7. The types of Tephrite are Igneous rock whereas types of Pseudotachylite are Cataclastic rock. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Tephrite is bluish black while that of Pseudotachylite is light to dark brown. The specific heat capacity of Tephrite is 0.92 kJ/Kg K and that of Pseudotachylite is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Tephrite is heat resistant, impact resistant whereas Pseudotachylite is heat resistant.