1 Definition
1.1 Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From Greek tephra, ashes from Indo-European base, to burn
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
1.4 Class
Igneous Rocks
Metamorphic Rocks
1.4.1 Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
2 Texture
2.1 Texture
Aphanitic to Porphyritic
Earthy, Mud-rich, Rough
2.2 Color
Black, Brown, Colourless, Green, Grey, White
Black, Brown, Colourless, Green, Grey, White
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
3.1.2 Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
Landscaping
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
3.2.2 Medical Industry
Not Yet Used
Not Applicable
3.3 Antiquity Uses
Artifacts, Sculpture
Artifacts, Monuments, Sculpture
3.4 Other Uses
3.4.1 Commercial Uses
Production of Lime, Soil Conditioner
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
4 Types
4.1 Types
4.2 Features
Host Rock for Lead
Host Rock for Lead, Zinc and Copper Deposits
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Not Applicable
Data Not Available
4.3.3 Sculpture
4.3.4 Famous Sculptures
Data Not Available
Data Not Available
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 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.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
5.2 Composition
5.2.1 Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
5.2.2 Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Not Applicable
5.3.5 Erosion
5.3.6 Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Not Applicable
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Medium to Fine Coarse Grained
Fine Grained
6.1.3 Fracture
6.1.4 Streak
Bluish Black
Light to dark brown
6.1.5 Porosity
Very Less Porous
Less Porous
6.1.6 Luster
Subvitreous to Dull
Waxy and Dull
6.1.7 Compressive Strength
4.3.2 Cleavage
Crenulation and Pervasive
Slaty
4.3.4 Toughness
4.3.6 Specific Gravity
6.1.2 Transparency
6.1.3 Density
2.8-2.9 g/cm32.8-2.9 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
0.92 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
6.2.5 Resistance
Heat Resistant, Impact Resistant
Heat Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
Not Yet Found
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
7.1.2 Africa
Namibia, Uganda
South Africa, Western Africa
7.1.3 Europe
Germany, Hungary, Italy, Portugal, Spain
United Kingdom
7.1.4 Others
Not Yet Found
Not Yet Found
7.2 Deposits in Western Continents
7.2.1 North America
7.2.2 South America
Not Yet Found
Brazil, Colombia, Paraguay
7.3 Deposits in Oceania Continent
7.3.1 Australia
New Zealand, Western Australia
Central Australia, Western Australia