Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Basaltic Trachyandesite is an extrusive igneous rock which is a type of Basalt rock and is formed by the rapid cooling of basaltic lava exposed at or very near the Earth's surface
Discoverer
Van Tooren
Unknown
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From its mineral and compound content and its relation with Basalt and Andesite rock
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Color
Black, Brown, Colourless, Green, Grey, White
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Vesicular
Dull and Soft
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Floor Tiles, Homes, Hotels, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing, Whetstones
Construction Industry
Landscaping
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture
Artifacts, Monuments
Commercial Uses
Production of Lime, Soil Conditioner
An Oil and Gas Reservoir, Commemorative Tablets, Creating Artwork
Types
Not Available
Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite
Features
Host Rock for Lead
Has High structural resistance against erosion and climate, Very fine grained rock
Archaeological Significance
Monuments
Not Yet Used
Not Yet Used
Famous Monuments
Not Applicable
Not Applicable
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
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.
Basaltic Trachandesite is a fine-grained, hard rock that forms when bits of lava shoot out of volcanoes.
Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Olivine, Plagioclase, Pyroxene
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Not Available
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Uneven
Conchoidal
Streak
Bluish Black
White to Grey
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Not Available
Cleavage
Crenulation and Pervasive
Not Available
Specific Gravity
2.86
2.8-3
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
2.9-3.1 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
India, Russia
Africa
Namibia, Uganda
South Africa
Europe
Germany, Hungary, Italy, Portugal, Spain
Iceland
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Canada, USA
South America
Not Yet Found
Brazil
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
Not Yet Found
All about Tephrite and Basaltic Trachyandesite Properties
Know all about Tephrite and Basaltic Trachyandesite properties here. All properties of rocks are important as they define the type of rock and its application. Tephrite and Basaltic Trachyandesite belong to Igneous Rocks.Texture of Tephrite is Aphanitic to Porphyritic whereas that of Basaltic Trachyandesite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular. Tephrite appears Vesicular and Basaltic Trachyandesite appears Dull and Soft. The luster of Tephrite is subvitreous to dull while that of Basaltic Trachyandesite is not available. Tephrite is available in black, brown, colourless, green, grey, white colors whereas Basaltic Trachyandesite is available in black, brown, light to dark grey colors. The commercial uses of Tephrite are production of lime, soil conditioner and that of Basaltic Trachyandesite are an oil and gas reservoir, commemorative tablets, creating artwork.