Definition
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds
  
Troctolite is a mafic intrusive rock type. It consists essentially of major but variable amounts of olivine and calcic plagioclase along with minor pyroxene. It is an olivine-rich anorthosite, or a pyroxene-depleted relative of gabbro
  
History
  
  
Origin
USA
  
Unknown
  
Discoverer
John Peter Salley
  
Christian Leopold von Buch
  
Etymology
From the Old English term col, which has meant mineral of fossilized carbon since the 13th century
  
From German Troklotit, from Greek trōktēs, a marine fish (taken to be trout)
  
Class
Sedimentary Rocks
  
Igneous Rocks
  
Sub-Class
Durable Rock, Soft Rock
  
Durable Rock, Hard Rock
  
Family
  
  
Group
Not Applicable
  
Plutonic
  
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Coarse Grained Rock, Opaque Rock
  
Texture
Amorphous, Glassy
  
Phaneritic
  
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
  
Dark Grey to Black
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
No
  
Yes
  
Scratch Resistant
No
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
No
  
Yes
  
Acid Resistant
No
  
Yes
  
Appearance
Veined or Pebbled
  
Veined and Shiny
  
Architecture
  
  
Interior Uses
Not Yet Used
  
Bathrooms, Countertops, Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration, Kitchens
  
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
  
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts
  
Artifacts, Jewellery, Monuments, Sculpture
  
Other Uses
  
  
Commercial Uses
Alumina Refineries, Electricity Generation, Liquid Fuel, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Paper Industry
  
Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
  
Types
Peat, Lignite, Sub-Bituminous Coal, Bituminous Coal, Anthracite, Graphite
  
Not Available
  
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
  
Used
  
Famous Sculptures
Not Applicable
  
Data Not Available
  
Pictographs
Not Used
  
Not Used
  
Petroglyphs
Not Used
  
Not Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Present
  
Absent
  
Formation
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.
  
Troctolite 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.
  
Composition
  
  
Mineral Content
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
  
Augite, Olivine, Plagioclase, Pyroxene
  
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
  
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Weathering
No
  
Yes
  
Types of Weathering
Not Applicable
  
Mechanical Weathering
  
Erosion
No
  
Yes
  
Types of Erosion
Not Applicable
  
Chemical Erosion, Coastal Erosion, Water Erosion
  
Physical Properties
  
  
Hardness
1-1.5
  
7
  
Grain Size
Medium to Fine Coarse Grained
  
Coarse Grained
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
Black
  
Black
  
Porosity
Less Porous
  
Highly Porous
  
Luster
Dull to Vitreous to Submetallic
  
Not Available
  
Compressive Strength
Not Available
  
225.00 N/mm
2
  
7
Cleavage
Non-Existent
  
Not Available
  
Toughness
Not Available
  
1.6
  
Specific Gravity
1.1-1.4
  
2.86-2.87
  
Transparency
Opaque
  
Opaque
  
Density
1100-1400 g/cm3
  
2.7-3.3 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
1.32 kJ/Kg K
  
4
Not Available
  
Resistance
Heat Resistant
  
Impact Resistant, Pressure Resistant, Wear Resistant
  
Deposits in Eastern Continents
  
  
Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
  
India, Russia
  
Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
  
South Africa
  
Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
  
Germany, Greece, Italy, Scotland, Turkey
  
Others
Not Yet Found
  
Greenland
  
Deposits in Western Continents
  
  
North America
Canada, Mexico, USA
  
Canada, USA
  
South America
Brazil, Chile, Colombia, Venezuela
  
Brazil, Colombia, Venezuela
  
Deposits in Oceania Continent
  
  
Australia
New South Wales, Queensland, Victoria
  
New Zealand, Queensland