Definition
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Discoverer
John Peter Salley
Unknown
Etymology
From the Old English term col, which has meant mineral of fossilized carbon since the 13th century
From German Grauwacke, from grau grey + wacke
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Group
Not Applicable
Not Applicable
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Amorphous, Glassy
Clastic
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Beige, Black, Brown, Colourless, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Durability
Durable
Durable
Appearance
Veined or Pebbled
Dull
Interior Uses
Not Yet Used
Decorative Aggregates, Floor Tiles, 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, Whetstones
Construction Industry
Cement Manufacture, for Road Aggregate, Making natural cement, Steel Production
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts, Sculpture, Small Figurines
Commercial Uses
Alumina Refineries, Electricity Generation, Liquid Fuel, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Paper Industry
As armour rock for sea walls, Petroleum reservoirs, 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
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Archaeological Significance
Monuments
Not Yet Used
Not Yet Used
Famous Monuments
Not Applicable
Not Applicable
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
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.
Graywacke rock is a type of sedimentary rock, which is also known as immature sandstone, which is indurated, dark grey and consisting of poorly sorted angular to sub-angular, sand-sized grains.
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, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Aluminium Oxide, NaCl, CaO, Chromium(III) Oxide, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Not Applicable
Types of Weathering
Not Applicable
Biological Weathering, Chemical Weathering
Types of Erosion
Not Applicable
Coastal Erosion, Sea Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Angular and Fine
Fracture
Conchoidal
Conchoidal
Porosity
Less Porous
Highly Porous
Luster
Dull to Vitreous to Submetallic
Dull
Cleavage
Non-Existent
Perfect
Toughness
Not Available
2.6
Specific Gravity
1.1-1.4
2.2-2.8
Transparency
Opaque
Opaque
Density
1100-1400 g/cm3
2.6-2.61 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Namibia, Nigeria, South Africa
Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Others
Not Yet Found
Greenland
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Brazil, Chile, Colombia, Venezuela
Brazil
Deposits in Oceania Continent
Australia
New South Wales, Queensland, Victoria
New South Wales, New Zealand
Coal vs Greywacke Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Coal vs Greywacke characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Coal and Properties of Greywacke. Learn more about Coal vs Greywacke in the next section. The interior uses of Coal include Not yet used whereas the interior uses of Greywacke include Decorative aggregates, Floor tiles, Flooring, Homes and Interior decoration. Due to some exceptional properties of Coal and Greywacke, they have various applications in construction industry. The uses of Coal in construction industry include Cement manufacture, For road aggregate, Making natural cement, Steel production and that of Greywacke include Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate, Raw material for the manufacture of mortar.
More about Coal and Greywacke
Here you can know more about Coal and Greywacke. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Coal and Greywacke consists of mineral content and compound content. The mineral content of Coal includes 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 and mineral content of Greywacke includes Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz. You can also check out the list of all . When we have to compare Coal vs Greywacke, the texture, color and appearance plays an important role in determining the type of rock. Coal is available in black, brown, dark brown, grey, light to dark grey colors whereas, Greywacke is available in beige, black, brown, colourless, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors. Appearance of Coal is Veined or Pebbled and that of Greywacke is Dull. Properties of rock is another aspect for Coal vs Greywacke. The hardness of Coal is 1-1.5 and that of Greywacke is 6-7. The types of Coal are Peat, Lignite, Sub-Bituminous Coal, Bituminous Coal, Anthracite, Graphite whereas types of Greywacke are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Coal is black while that of Greywacke is white. The specific heat capacity of Coal is 1.32 kJ/Kg K and that of Greywacke is Not Available. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Coal is heat resistant whereas Greywacke is heat resistant, impact resistant, pressure resistant.