Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Blueschist is a metamorphic rock which is generally blue in color and is formed under conditions of high pressure and low temperature
Discoverer
Unknown
Edgar Bailey
Etymology
From French, Latin lignum wood + -ite1
From French schiste, Greek skhistos i.e. split
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
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Amorphous, Glassy
Foliated
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Blue, Bluish - Grey, Purple, Shades of Blue
Durability
Durable
Durable
Appearance
Veined or Pebbled
Dull and Banded
Interior Uses
-
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Exterior Uses
-
Garden Decoration, Office Buildings
Other Architectural Uses
-
-
Construction Industry
for Road Aggregate, Steel Production
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Antiquity Uses
-
Artifacts, Monuments, Sculpture
Commercial Uses
Electricity Generation
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Tombstones
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
Has High structural resistance against erosion and climate, Very fine grained 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.
Blueschist forms due to the metamorphism of basalt and other rocks with similar composition at high pressures and low temperatures and approximately corresponding to a depth of 15 to 30 kilometers and 200 to 500 °C.
Mineral Content
-
Albite, Chlorite, Epidote, Garnet, Glaucophane, Lawsonite, Muscovite or Illite, Quartz
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
-
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical 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
Fine to Medium Grained
Fracture
Conchoidal
Conchoidal
Streak
Black
White to Grey
Porosity
Highly Porous
Highly Porous
Luster
Dull to Vitreous to Submetallic
Dull
Specific Gravity
1.1-1.4
3-3.2
Transparency
Opaque
Opaque
Density
800-801 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant
Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
Japan, Turkey
Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Egypt, Ethiopia, South Africa
Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
France, Greece, Iceland
Deposits in Western Continents
North America
Canada, Mexico, USA
USA
South America
Brazil, Chile, Colombia, Venezuela
-
Deposits in Oceania Continent
Australia
New South Wales, Queensland, Victoria
New Zealand