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Anthracite and Hornfels


Hornfels and Anthracite


Definition

Definition
Anthracite is a type of sedimentary rock which is hard and is variety of coal that has high luster   
Hornfels is a metamorphic rock formed by the contact between mudstone or other clay rich rock, and a hot igneous body, and represents a heat altered equivalent of the original rock   

History
  
  

Origin
Pennsylvania, U.S.   
New Zealand   

Discoverer
Unknown   
Unknown   

Etymology
From Greek anthrakites, from anthrax, anthrak meaning coal   
From German which means hornstone   

Class
Metamorphic Rocks   
Metamorphic Rocks   

Sub-Class
Durable Rock, Soft Rock   
Durable Rock, Soft Rock   

Family
  
  

Group
Not Applicable   
Not Applicable   

Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock   
Fine Grained Rock, Opaque Rock   

Texture

Texture
Amorphous, Glassy   
Granular, Platy   

Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey   
Brown, Dark Greenish - Grey, Green, Reddish Brown   

Maintenance
Less   
Less   

Durability
Durable   
Durable   

Water Resistant
No   
Yes   

Scratch Resistant
No   
No   

Stain Resistant
No   
No   

Wind Resistant
No   
No   

Acid Resistant
No   
No   

Appearance
Veined or Pebbled   
Dull   

Uses

Architecture
  
  

Interior Uses
Not Yet Used   
Decorative Aggregates, Flooring, Homes, Interior Decoration   

Exterior Uses
Not Yet Used   
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone   

Other Architectural Uses
Not Yet Used   
Curbing   

Industry
  
  

Construction Industry
Cement Manufacture, for Road Aggregate, Making natural cement, Steel Production   
for Road Aggregate, Roadstone   

Medical Industry
In Chemical and Pharmaceutical Industry, Manufacture of Aspirins   
Not Yet Used   

Antiquity Uses
Not Yet Used   
Artifacts, Monuments   

Other Uses
  
  

Commercial Uses
Alumina Refineries, Electricity Generation, Liquid Fuel, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Paper Industry   
Cemetery Markers, Commemorative Tablets, Creating Artwork   

Types

Types
Semi-anthracite and Meta-anthracite   
Biotite hornfels   

Features
Helps in production of Heat and Electricity, Used as fossil fuel   
Smooth to touch   

Archaeological Significance
  
  

Monuments
Not Yet Used   
Used   

Famous Monuments
Not Applicable   
Data Not Available   

Sculpture
Not Yet Used   
Not Yet Used   

Famous Sculptures
Not Applicable   
Not Applicable   

Pictographs
Used   
Used   

Petroglyphs
Used   
Used   

Figurines
Not Yet Used   
Not Yet Used   

Fossils
Absent   
Absent   

Formation

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.   
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Hornfels is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.   

Composition
  
  

Mineral Content
Calcite, Clay, Clay Minerals   
Andalusite   

Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur   
Fe, Mg   

Transformation
  
  

Metamorphism
Yes   
No   

Types of Metamorphism
Burial Metamorphism, Contact Metamorphism, Regional Metamorphism   
Not Applicable   

Weathering
No   
Yes   

Types of Weathering
Not Applicable   
Biological Weathering   

Erosion
No   
Yes   

Types of Erosion
Not Applicable   
Chemical Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion   

Properties

Physical Properties
  
  

Hardness
1-1.5   
2-3   

Grain Size
Medium to Fine Coarse Grained   
Fine Grained   

Fracture
Conchoidal   
Conchoidal   

Streak
Black   
Unknown   

Porosity
Less Porous   
Highly Porous   

Luster
Shiny   
Shiny   

Compressive Strength
Not Available   
5.80 N/mm2   
31

Cleavage
Non-Existent   
Perfect   

Toughness
Not Available   
Not Yet Found   

Specific Gravity
1.1-1.4   
3.4-3.9   

Transparency
Opaque   
Opaque   

Density
1.25-2.5 g/cm3   
0.25-0.30 g/cm3   

Thermal Properties
  
  

Specific Heat Capacity
1.32 kJ/Kg K   
4
0.84 kJ/Kg K   
15

Resistance
Heat Resistant, Water Resistant   
Heat Resistant, Impact Resistant, Pressure Resistant   

Reserves

Deposits in Eastern Continents
  
  

Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam   
Bangladesh, Bhutan, China, India, North Korea, Qatar, Russia, Saudi Arabia, South Korea, Thailand   

Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania   
Cameroon, East Africa, Tanzania, Western Africa   

Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom   
United Kingdom   

Others
Not Yet Found   
Not Yet Found   

Deposits in Western Continents
  
  

North America
Canada, Mexico, USA   
Canada, USA   

South America
Brazil, Chile, Colombia, Venezuela   
Bolivia, Brazil, Colombia, Ecuador   

Deposits in Oceania Continent
  
  

Australia
New South Wales, Queensland, Victoria   
New South Wales, New Zealand, Queensland, Western Australia   

Summary >>
<< Reserves

All about Anthracite and Hornfels Properties

Know all about Anthracite and Hornfels properties here. All properties of rocks are important as they define the type of rock and its application. Anthracite and Hornfels belong to Metamorphic Rocks.Texture of Anthracite is Amorphous, Glassy whereas that of Hornfels is Granular, Platy. Anthracite appears Veined or Pebbled and Hornfels appears Dull. The luster of Anthracite and Hornfels is shiny. Anthracite is available in black, brown, dark brown, grey, light to dark grey colors whereas Hornfels is available in brown, dark greenish - grey, green, reddish brown 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 Hornfels are cemetery markers, commemorative tablets, creating artwork.

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