Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Metapelite is an old and currently not widely used field geological term for a clay rich fine-grained clastic sediment or sedimentary rock, i.e. mud or a mudstone
Discoverer
Unknown
Unknown
Etymology
From French, Latin lignum wood + -ite1
From Pelos or clay in Greek
Class
Sedimentary Rocks
Metamorphic 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
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Amorphous, Glassy
Foliated
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Dark Greenish - Grey, Green, Light Green, Light Greenish Grey
Durability
Durable
Durable
Appearance
Veined or Pebbled
Banded
Interior Uses
-
Decorative Aggregates, Interior Decoration
Exterior Uses
-
As Building Stone, As Facing Stone
Other Architectural Uses
-
Curbing
Construction Industry
for Road Aggregate, Steel Production
Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
-
Artifacts
Commercial Uses
Electricity Generation
Commemorative Tablets, Creating Artwork
Types
Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite
Metamorphic rock
Features
Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel
Easily splits into thin plates, It is One of the Oldest, Strongest and Hardest Rock
Archaeological Significance
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.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Metapelite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
-
Albite, Chlorite, Quartz
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Aluminium Oxide, CaO, MgO
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, Water Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Medium to Fine Coarse Grained
Fracture
Conchoidal
Fibrous
Porosity
Highly Porous
Highly Porous
Luster
Dull to Vitreous to Submetallic
Earthy
Specific Gravity
1.1-1.4
3.4-3.7
Transparency
Opaque
Opaque
Density
800-801 g/cm3
0-300 g/cm3
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
-
Africa
Botswana, Kenya, Morocco, Mozambique, South 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
Deposits in Western Continents
North America
Canada, Mexico, USA
-
South America
Brazil, Chile, Colombia, Venezuela
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New South Wales, Queensland, Victoria
Central Australia, Western Australia