Definition
Metapelite is an old and currently not widely used field geological term for a clay rich fine-grained clastic sediment or sedimentary rock, i.e. mud or a mudstone
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Discoverer
Unknown
Van Tooren
Etymology
From Pelos or clay in Greek
From Greek tephra, ashes from Indo-European base, to burn
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Foliated
Aphanitic to Porphyritic
Color
Dark Greenish - Grey, Green, Light Green, Light Greenish Grey
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded
Vesicular
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate
Landscaping
Antiquity Uses
Artifacts
Artifacts, Sculpture
Commercial Uses
Commemorative Tablets, Creating Artwork
Production of Lime, Soil Conditioner
Types
Metamorphic rock
Igneous rock
Features
Easily splits into thin plates, It is One of the Oldest, Strongest and Hardest Rock
Host Rock for Lead
Archaeological Significance
Formation
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Metapelite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
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.
Mineral Content
Albite, Chlorite, Quartz
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, CaO, MgO
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Types of Metamorphism
-
Cataclastic Metamorphism, Contact 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, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Grain Size
Medium to Fine Coarse Grained
Medium to Fine Coarse Grained
Porosity
Highly Porous
Very Less Porous
Luster
Earthy
Subvitreous to Dull
Cleavage
-
Crenulation and Pervasive
Specific Gravity
3.4-3.7
2.86
Transparency
Opaque
Opaque
Density
0-300 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Africa
Western Africa
Namibia, Uganda
Europe
United Kingdom
Germany, Hungary, Italy, Portugal, Spain
Deposits in Western Continents
South America
Brazil, Colombia, Ecuador
-
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New Zealand, Western Australia
All about Metapelite and Tephrite Properties
Know all about Metapelite and Tephrite properties here. All properties of rocks are important as they define the type of rock and its application. Metapelite belongs to Metamorphic Rocks while Tephrite belongs to Igneous Rocks.Texture of Metapelite is Foliated whereas that of Tephrite is Aphanitic to Porphyritic. Metapelite appears Banded and Tephrite appears Vesicular. The luster of Metapelite is earthy while that of Tephrite is subvitreous to dull. Metapelite is available in dark greenish - grey, green, light green, light greenish grey colors whereas Tephrite is available in black, brown, green, grey, white colors. The commercial uses of Metapelite are commemorative tablets, creating artwork and that of Tephrite are production of lime, soil conditioner.