Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Rhyodacite is an extrusive volcanic rock intermediate in composition between dacite and rhyolite
Discoverer
Van Tooren
Unknown
Etymology
From Greek tephra, ashes from Indo-European base, to burn
Rhyo lite + dacite : a rock intermediate between rhyolite and dacite that is the extrusive equivalent of granodiorite
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
Earthy
Color
Black, Brown, Green, Grey, White
Black to Grey, Dark Greenish - Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Vesicular
Skeletal
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
Landscaping
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
Antiquity Uses
Artifacts, Sculpture
Artifacts
Commercial Uses
Production of Lime, Soil Conditioner
Cemetery Markers, Creating Artwork
Types
Igneous rock
Intermediate volcanic rock
Features
Host Rock for Lead
Available in Lots of Colors and Patterns
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.
Rhyodacite 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
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Ca, Fe, Potassium Oxide, Potassium, Silicon Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Uneven
Conchoidal
Streak
Bluish Black
Black
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Greasy to Dull
Cleavage
Crenulation and Pervasive
-
Specific Gravity
2.86
2.34-2.40
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
-9999 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
-
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
Namibia, Uganda
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Germany, Hungary, Italy, Portugal, Spain
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland
Deposits in Western Continents
North America
USA
Canada, USA
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
-
Tephrite vs Rhyodacite 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 Rhyodacite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Tephrite and Properties of Rhyodacite. Learn more about Tephrite vs Rhyodacite in the next section. The interior uses of Tephrite include Decorative aggregates, Flooring, Homes and Interior decoration whereas the interior uses of Rhyodacite include Decorative aggregates and Interior decoration. Due to some exceptional properties of Tephrite and Rhyodacite, they have various applications in construction industry. The uses of Tephrite in construction industry include Landscaping and that of Rhyodacite include As dimension stone, Construction aggregate, For road aggregate, Landscaping.
More about Tephrite and Rhyodacite
Here you can know more about Tephrite and Rhyodacite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Tephrite and Rhyodacite consists of mineral content and compound content. The mineral content of Tephrite includes Alkali feldspar, Nepheline, Plagioclase, Pyroxene and mineral content of Rhyodacite includes Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon. You can also check out the list of all Igneous Rocks. When we have to compare Tephrite vs Rhyodacite, 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, Rhyodacite is available in black to grey, dark greenish - grey colors. Appearance of Tephrite is Vesicular and that of Rhyodacite is Skeletal. Properties of rock is another aspect for Tephrite vs Rhyodacite. The hardness of Tephrite is 6.5 and that of Rhyodacite is 5.5-6. The types of Tephrite are Igneous rock whereas types of Rhyodacite are Intermediate volcanic 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 Rhyodacite is black. The specific heat capacity of Tephrite is 0.92 kJ/Kg K and that of Rhyodacite is 1.12 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 Rhyodacite is heat resistant.