Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds
Discoverer
Van Tooren
John Peter Salley
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From the Old English term col, which has meant mineral of fossilized carbon since the 13th century
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft 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
Amorphous, Glassy
Color
Black, Brown, Green, Grey, White
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Durability
Durable
Durable
Appearance
Vesicular
Veined or Pebbled
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
-
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
-
Other Architectural Uses
Curbing
-
Construction Industry
Landscaping
Cement Manufacture, for Road Aggregate, Making natural cement, Steel Production
Antiquity Uses
Artifacts, Sculpture
Artifacts
Commercial Uses
Production of Lime, Soil Conditioner
Alumina Refineries, Electricity Generation, Liquid Fuel, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Paper Industry
Types
Igneous rock
Peat, Lignite, Sub-Bituminous Coal, Bituminous Coal, Anthracite, Graphite
Features
Host Rock for Lead
Helps in production of Heat and Electricity, Used as fossil fuel
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.
Coal forms from the accumulation of plant debris in a swamp environment which is buried by sediments such as mud or sand and then compacted to form coal.
Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Analcime, Apatite, Barite, Calcite, Chalcopyrite, Chlorite, Chromite, Clausthalite, Clay Minerals, Crandallite Group, Dolomite, Feldspar, Galena, Gypsum, Marcasite, Muscovite or Illite, Pyrite, Quartz, Siderite, Sphalerite, Zircon
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
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
Black
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Dull to Vitreous to Submetallic
Cleavage
Crenulation and Pervasive
-
Specific Gravity
2.86
1.1-1.4
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
1100-1400 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
-
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
Africa
Namibia, Uganda
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Europe
Germany, Hungary, Italy, Portugal, Spain
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Deposits in Western Continents
North America
USA
Canada, Mexico, USA
South America
-
Brazil, Chile, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New South Wales, Queensland, Victoria
All about Tephrite and Coal Properties
Know all about Tephrite and Coal properties here. All properties of rocks are important as they define the type of rock and its application. Tephrite belongs to Igneous Rocks while Coal belongs to Sedimentary Rocks.Texture of Tephrite is Aphanitic to Porphyritic whereas that of Coal is Amorphous, Glassy. Tephrite appears Vesicular and Coal appears Veined or Pebbled. The luster of Tephrite is subvitreous to dull while that of Coal is dull to vitreous to submetallic. Tephrite is available in black, brown, green, grey, white colors whereas Coal is available in black, brown, dark brown, grey, light to dark grey colors. The commercial uses of Tephrite are production of lime, soil conditioner and that of Coal are alumina refineries, electricity generation, liquid fuel, manufacture of soap, solvents, dyes, plastics and fibres, paper industry.