Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
Discoverer
Unknown
Johann Gottlob Lehmann
Etymology
From French, Latin lignum wood + -ite1
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Amorphous, Glassy
Clastic, Splintery
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Black, Brown, Buff, Green, Grey, Red, Yellow
Durability
Durable
Durable
Appearance
Veined or Pebbled
Muddy
Interior Uses
-
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
-
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
-
Curbing
Construction Industry
for Road Aggregate, Steel Production
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
-
Artifacts, Sculpture
Commercial Uses
Electricity Generation
Creating Artwork, Pottery
Types
Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Features
Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Archaeological Significance
Famous Monuments
-
Jantar Mantar in India
Formation
Coal formation takes place due to accumulation of plant debris in a swamp environment. The Coal formation process continues, as peat turns into lignite brown or black coal at increasing heat and pressure.
Shale forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are later compacted hence forming shale.
Mineral Content
-
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Ca, Fe, Mg, Silicon Dioxide, Sodium
Types of Metamorphism
-
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Medium to Fine Coarse Grained
Very fine-grained
Porosity
Highly Porous
Highly Porous
Luster
Dull to Vitreous to Submetallic
Dull
Specific Gravity
1.1-1.4
2.2-2.8
Transparency
Opaque
Opaque
Density
800-801 g/cm3
2.4-2.8 g/cm3
Resistance
Heat Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
Bangladesh, China, India, Russia
Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Deposits in Western Continents
North America
Canada, Mexico, USA
USA
South America
Brazil, Chile, Colombia, Venezuela
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, Queensland, Victoria
New South Wales, New Zealand, Queensland, Victoria, Western Australia