Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Adakite is an intermediate to felsic volcanic rock that has geochemical characteristics of magma which is said to be formed by partial melting of altered basalt that is subducted below volcanic arcs
Origin
Germany
Adak, Aleutian Islands
Discoverer
Van Tooren
Defant and Drummond
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From Adak, Aleutian Islands
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, Medium Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Porphyritic
Color
Black, Brown, Colourless, Green, Grey, White
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Appearance
Vesicular
Dull and Soft
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Floor Tiles, Homes, Hotels, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
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
Monuments, Sculpture, Small Figurines
Commercial Uses
Production of Lime, Soil Conditioner
Commemorative Tablets, Pottery, Used in aquariums
Types
Not Available
Not Available
Features
Host Rock for Lead
Has High structural resistance against erosion and climate, Host rock for Diamond, Very fine grained rock
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
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.
Adakite rocks are formed when the hydrous fluids are released from minerals that break down in metamorphosed basalt, and rise into the mantle they initiate partial melting.
Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Olivine, Plagioclase, Pyroxene
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Aluminium Oxide, MgO, Silicon Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Coastal Erosion, Sea Erosion, Water Erosion
Grain Size
Medium to Fine Coarse Grained
Fine to Medium Grained
Fracture
Uneven
Conchoidal
Streak
Bluish Black
Bluish Black
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Grainy, Pearly and Vitreous
Compressive Strength
Not Available
Cleavage
Crenulation and Pervasive
Not Available
Toughness
2.4
Not Available
Specific Gravity
2.86
Not Available
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
Not Available
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
India, Russia
Africa
Namibia, Uganda
Ethiopia, Somalia, 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
Tephrite vs Adakite 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 Adakite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Tephrite and Properties of Adakite. Learn more about Tephrite vs Adakite in the next section. The interior uses of Tephrite include Decorative aggregates, Flooring, Homes and Interior decoration whereas the interior uses of Adakite include Decorative aggregates, Floor tiles, Homes, Hotels and Kitchens. Due to some exceptional properties of Tephrite and Adakite, they have various applications in construction industry. The uses of Tephrite in construction industry include Landscaping and that of Adakite include As dimension stone, Cobblestones, Rail track ballast, Roadstone.
More about Tephrite and Adakite
Here you can know more about Tephrite and Adakite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Tephrite and Adakite consists of mineral content and compound content. The mineral content of Tephrite includes Alkali feldspar, Nepheline, Plagioclase, Pyroxene and mineral content of Adakite includes Olivine, Plagioclase, Pyroxene. You can also check out the list of all Igneous Rocks. When we have to compare Tephrite vs Adakite, the texture, color and appearance plays an important role in determining the type of rock. Tephrite is available in black, brown, colourless, green, grey, white colors whereas, Adakite is available in black, brown, light to dark grey colors. Appearance of Tephrite is Vesicular and that of Adakite is Dull and Soft. Properties of rock is another aspect for Tephrite vs Adakite. The hardness of Tephrite is 6.5 and that of Adakite is 3-4. The types of Tephrite are Not Available whereas types of Adakite are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Tephrite and Adakite is bluish black. The specific heat capacity of Tephrite is 0.92 kJ/Kg K and that of Adakite is Not Available. 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 Adakite is heat resistant, pressure resistant, wear resistant.