Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Jasperoid is a rare, peculiar type of metasomatic alteration of rocks
Discoverer
Van Tooren
Unknown
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From silica, the main mineral content of Jasperoid
Class
Igneous Rocks
Sedimentary 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
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Earthy
Color
Black, Brown, Green, Grey, White
Black, Brown, Green, Grey, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Vesicular
Glassy or Pearly
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
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, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories, Production of Glass and Ceramics, Serves as an Oil and Gas Reservoir rock
Medical Industry
-
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts, Sculpture
Artifacts, Jewellery, Monuments, Sculpture
Commercial Uses
Production of Lime, Soil Conditioner
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO)
Features
Host Rock for Lead
Host Rock for Lead, Traps for subsurface fluids like Oil and Natural Gas., Zinc and Copper Deposits
Archaeological Significance
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.
Jasperoid is a rare and peculiar type of metasomatic alteration of rocks. It is formed by extreme alteration of wall rocks within a shear zone which may occur in sediments, andesites, trachytes and basalts.
Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Clay Minerals, Pyrite, Quartz, Sulfides
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
NaCl, CaO, Carbon Dioxide, Magnesium Carbonate, MgO
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
-
Grain Size
Medium to Fine Coarse Grained
Medium to Fine Coarse Grained
Fracture
Uneven
Conchoidal
Streak
Bluish Black
White
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Vitreous and Pearly
Cleavage
Crenulation and Pervasive
Perfect
Specific Gravity
2.86
2.8-3
Transparency
Opaque
Transparent to Translucent
Density
2.8-2.9 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Africa
Namibia, Uganda
Morocco, Namibia
Europe
Germany, Hungary, Italy, Portugal, Spain
Austria, Italy, Romania, Spain, Switzerland
Deposits in Western Continents
North America
USA
Mexico, USA
South America
-
Brazil, Colombia
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New South Wales, Queensland, Yorke Peninsula
All about Tephrite and Jasperoid Properties
Know all about Tephrite and Jasperoid properties here. All properties of rocks are important as they define the type of rock and its application. Tephrite belongs to Igneous Rocks while Jasperoid belongs to Sedimentary Rocks.Texture of Tephrite is Aphanitic to Porphyritic whereas that of Jasperoid is Earthy. Tephrite appears Vesicular and Jasperoid appears Glassy or Pearly. The luster of Tephrite is subvitreous to dull while that of Jasperoid is vitreous and pearly. Tephrite is available in black, brown, green, grey, white colors whereas Jasperoid is available in black, brown, green, grey, pink, white colors. The commercial uses of Tephrite are production of lime, soil conditioner and that of Jasperoid are an oil and gas reservoir, as a feed additive for livestock, gemstone, metallurgical flux, production of lime, soil conditioner, source of magnesia (mgo).