Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Discoverer
Van Tooren
Alexandre Brongniart and René Just Haüy
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From Greek trakhus rough’ or trakhutēs roughness
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
Aphanitic to Porphyritic
Color
Black, Brown, Colourless, Green, Grey, White
Black, Brown, Dark Greenish - Grey, Green, Grey, Light to Dark Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Vesicular
Banded
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
Landscaping
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Production of Lime, Soil Conditioner
Cemetery Markers, Creating Artwork
Types
Not Available
Not Available
Features
Host Rock for Lead
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
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.
Trachyte is an igneous volcanic rock with an aphanitic to porphyritic texture. It is the volcanic equivalent of syenite rock and forms as a result of magmatic differentiation.
Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Augite, Biotite, Feldspar, Hornblade, Plagioclase, Quartz
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Potassium Oxide, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Contact 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, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Uneven
Not Available
Streak
Bluish Black
White
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Metallic
Cleavage
Crenulation and Pervasive
Not Available
Toughness
2.4
Not Available
Specific Gravity
2.86
2.7
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
2.43-2.45 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
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
Bulgaria, England, Germany, Norway, Romania, Switzerland
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
South America
Not Yet Found
Brazil, Chile
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New Zealand, Queensland, South Australia, Western Australia