Definition
Anthracite is a type of sedimentary rock which is hard and is variety of coal that has high luster
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Origin
Pennsylvania, U.S.
Germany
Discoverer
Unknown
Van Tooren
Etymology
From Greek anthrakites, from anthrax, anthrak meaning coal
From Greek tephra, ashes from Indo-European base, to burn
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft 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
Amorphous, Glassy
Aphanitic to Porphyritic
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Appearance
Veined or Pebbled
Vesicular
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
Cement Manufacture, for Road Aggregate, Making natural cement, Steel Production
Landscaping
Medical Industry
In Chemical and Pharmaceutical Industry, Manufacture of Aspirins
-
Antiquity Uses
-
Artifacts, Sculpture
Commercial Uses
Alumina Refineries, Electricity Generation, Liquid Fuel, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Paper Industry
Production of Lime, Soil Conditioner
Types
Semi-anthracite and Meta-anthracite
Igneous rock
Features
Helps in production of Heat and Electricity, Used as fossil fuel
Host Rock for Lead
Archaeological Significance
Formation
Anthracite forms from the accumulation of plant debris in a swamp environment. When plant debris dies and falls into the swamp, the standing water of the swamp protects it from decay.
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
Calcite, Clay, Clay Minerals
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Contact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact 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
Conchoidal
Uneven
Streak
Black
Bluish Black
Porosity
Less Porous
Very Less Porous
Luster
Shiny
Subvitreous to Dull
Cleavage
-
Crenulation and Pervasive
Specific Gravity
1.1-1.4
2.86
Transparency
Opaque
Opaque
Density
1.25-2.5 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Water Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
-
Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Namibia, Uganda
Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Germany, Hungary, Italy, Portugal, Spain
Deposits in Western Continents
North America
Canada, Mexico, USA
USA
South America
Brazil, Chile, Colombia, Venezuela
-
Deposits in Oceania Continent
Australia
New South Wales, Queensland, Victoria
New Zealand, Western Australia
All about Anthracite and Tephrite Properties
Know all about Anthracite and Tephrite properties here. All properties of rocks are important as they define the type of rock and its application. Anthracite belongs to Metamorphic Rocks while Tephrite belongs to Igneous Rocks.Texture of Anthracite is Amorphous, Glassy whereas that of Tephrite is Aphanitic to Porphyritic. Anthracite appears Veined or Pebbled and Tephrite appears Vesicular. The luster of Anthracite is shiny while that of Tephrite is subvitreous to dull. Anthracite is available in black, brown, dark brown, grey, light to dark grey colors whereas Tephrite is available in black, brown, green, grey, white colors. The commercial uses of Anthracite are alumina refineries, electricity generation, liquid fuel, manufacture of soap, solvents, dyes, plastics and fibres, paper industry and that of Tephrite are production of lime, soil conditioner.