Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Jadeitite is a metamorphic rock usually found in blueschist grade metamorphic terrains
History
Origin
Germany
-
Discoverer
Van Tooren
Unknown
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From pyroxene mineral jadeite
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
Volcanic
-
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, Brown, Green, Grey, White
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Vesicular
Rough and Dull
Architecture
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
Landscaping
As Dimension Stone, Cutting Tool, Knives
Medical Industry
-
-
Antiquity Uses
Artifacts, Sculpture
Artifacts, Jewellery, Monuments, Sculpture
Other Uses
Commercial Uses
Production of Lime, Soil Conditioner
Commemorative Tablets, Creating Artwork, Jewelry
Types
Igneous rock
Metamorphic rock
Features
Host Rock for Lead
Host Rock for Lead
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Absent
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. Jadeitite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Composition
Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Carbonate, Magnetite, Pyrrhotite, Serpentine, Sulfides
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Ca, CaO, Carbon Dioxide, KCl, MgO, Sulfur Dioxide, Sulphur
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Coastal Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
6.53-5
1
7
👆🏻
Grain Size
Medium to Fine Coarse Grained
Very fine-grained
Fracture
Uneven
Uneven
Streak
Bluish Black
White, Greenish White or Grey
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Waxy and Dull
Compressive Strength
90.00 N/mm2310.00 N/mm2
0.15
450
👆🏻
Cleavage
Crenulation and Pervasive
-
Toughness
2.4
7
Specific Gravity
2.862.79-3
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm32.5-3 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.92 kJ/Kg K0.95 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Water Resistant
Deposits in Eastern Continents
Asia
-
India, Saudi Arabia, Singapore, South Korea
Africa
Namibia, Uganda
Ethiopia, Western Africa
Europe
Germany, Hungary, Italy, Portugal, Spain
England, Georgia, Switzerland, United Kingdom
Others
-
-
Deposits in Western Continents
North America
USA
Canada
South America
-
Colombia
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
Central Australia, New South Wales, New Zealand, Western Australia