Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Mugearite is a type of oligoclase bearing basalt, also comprising of olivine, apatite, and opaque oxides
Origin
Germany
Skye, Scotland
Discoverer
Van Tooren
Alfred Harker
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From mugear + -ite
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
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, Flooring, Homes, Hotels
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, Cobblestones, Rail Track Ballast, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture
Artifacts, Monuments, Sculpture
Commercial Uses
Production of Lime, Soil Conditioner
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
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.
Mugearite forms when lava reaches the Earth's surface near an active volcano. The temperature of lava is between 1100 to 1250° C when it gets to the surface.
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
Burial Metamorphism, Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Not Applicable
Grain Size
Medium to Fine Coarse Grained
Not Applicable
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 Applicable
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 Mugearite Properties
Know all about Tephrite and Mugearite properties here. All properties of rocks are important as they define the type of rock and its application. Tephrite and Mugearite belong to Igneous Rocks.Texture of Tephrite is Aphanitic to Porphyritic whereas that of Mugearite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular. Tephrite appears Vesicular and Mugearite appears Dull and Soft. The luster of Tephrite is subvitreous to dull while that of Mugearite is not available. Tephrite is available in black, brown, colourless, green, grey, white colors whereas Mugearite is available in black, brown, light to dark grey colors. The commercial uses of Tephrite are production of lime, soil conditioner and that of Mugearite are creating artwork.