Definition
Marl is an unconsolidated sedimentary rock consisting of clay and lime
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers called coal beds
Discoverer
Unknown
John Peter Salley
Etymology
From Old French marle, from Late Latin marglia
From the Old English term col, which has meant mineral of fossilized carbon since the 13th century
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Soft Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Earthy
Amorphous, Glassy
Color
Beige, Brown, Green, Grey, White
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Durability
Durable
Durable
Appearance
Rough and Dull
Veined or Pebbled
Interior Uses
Decorative Aggregates, Floor Tiles
Not Yet Used
Exterior Uses
As Building Stone, Roof Tiles
Not Yet Used
Other Architectural Uses
Curbing
Not Yet Used
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Cement Manufacture, for Road Aggregate, Making natural cement, Steel Production
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Jewellery, Sculpture, Small Figurines
Artifacts
Commercial Uses
Creating Artwork, Soil Conditioner
Alumina Refineries, Electricity Generation, Liquid Fuel, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Paper Industry
Types
Clay Marl ,Blue Marl, Red Marl, High Bank Marl, Shell Layer Marl, Under Shell Layer Marl, Sand Marl, Green Marl, Grey Marl and Clayey Marl
Peat, Lignite, Sub-Bituminous Coal, Bituminous Coal, Anthracite, Graphite
Features
Generally rough to touch, Is one of the oldest rock, Splintery, Very fine grained rock
Helps in production of Heat and Electricity, Used as fossil fuel
Archaeological Significance
Monuments
Not Yet Used
Not Yet Used
Famous Monuments
Not Applicable
Not Applicable
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Figurines
Used
Not Yet Used
Formation
Marl forms when very fine-grained clay particles are deposited in water which settles at the bottom of water bodies and are compacted by overlying sediment; the water squeezes out and hence forming Marl rock.
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
Calcite, Clay, Dolomite, Gypsum, Micas, Pyrite, Quartz
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
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, Silicon Dioxide
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering
Not Applicable
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Not Applicable
Grain Size
Very fine-grained
Medium to Fine Coarse Grained
Fracture
Conchoidal
Conchoidal
Porosity
Highly Porous
Less Porous
Luster
Dull
Dull to Vitreous to Submetallic
Cleavage
Not Available
Non-Existent
Toughness
2.6
Not Available
Specific Gravity
2.2-2.8
1.1-1.4
Transparency
Opaque
Opaque
Density
2.4-2.8 g/cm3
1100-1400 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
India, Pakistan, Russia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
Africa
Ethiopia, Kenya, Morocco, South Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Canada, Mexico, USA
South America
Colombia, Ecuador, Peru
Brazil, Chile, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, Victoria, Western Australia
New South Wales, Queensland, Victoria
Marl vs Coal 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. Marl vs Coal characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Marl and Properties of Coal. Learn more about Marl vs Coal in the next section. The interior uses of Marl include Decorative aggregates and Floor tiles whereas the interior uses of Coal include Not yet used. Due to some exceptional properties of Marl and Coal, they have various applications in construction industry. The uses of Marl in construction industry include Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar and that of Coal include Cement manufacture, For road aggregate, Making natural cement, Steel production.
More about Marl and Coal
Here you can know more about Marl and Coal. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Marl and Coal consists of mineral content and compound content. The mineral content of Marl includes Calcite, Clay, Dolomite, Gypsum, Micas, Pyrite, Quartz and 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. You can also check out the list of all Sedimentary Rocks. When we have to compare Marl vs Coal, the texture, color and appearance plays an important role in determining the type of rock. Marl is available in beige, brown, green, grey, white colors whereas, Coal is available in black, brown, dark brown, grey, light to dark grey colors. Appearance of Marl is Rough and Dull and that of Coal is Veined or Pebbled. Properties of rock is another aspect for Marl vs Coal. The hardness of Marl is 2-3 and that of Coal is 1-1.5. The types of Marl are Clay Marl ,Blue Marl, Red Marl, High Bank Marl, Shell Layer Marl, Under Shell Layer Marl, Sand Marl, Green Marl, Grey Marl and Clayey Marl whereas types of Coal are Peat, Lignite, Sub-Bituminous Coal, Bituminous Coal, Anthracite, Graphite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Marl is white while that of Coal is black. The specific heat capacity of Marl is Not Available and that of Coal is 1.32 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Marl is heat resistant, impact resistant whereas Coal is heat resistant.