Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Pyroxenite is a dark, greenish, granular intrusive igneous rock consisting mainly of pyroxenes and olivine
History
Origin
France
-
Discoverer
Unknown
Unknown
Etymology
From French, Latin lignum wood + -ite1
From pyro- fire + Greek xenos stranger as the mineral group was new to igneous rocks
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Family
Group
-
Plutonic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Amorphous, Glassy
Clastic, Granular, Phaneritic, Porphyritic
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Black to Grey, Bluish - Grey, Dark Greenish - Grey, Green, Light Greenish Grey
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Veined or Pebbled
Layered, Banded, Veined and Shiny
Architecture
Interior Uses
-
Countertops, Decorative Aggregates, Interior Decoration, Kitchens
Exterior Uses
-
As Building Stone, As Facing Stone
Other Architectural Uses
-
Curbing
Industry
Construction Industry
for Road Aggregate, Steel Production
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
-
-
Antiquity Uses
-
Artifacts
Other Uses
Commercial Uses
Electricity Generation
Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Types
Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite
Clinopyroxenites, Orthopyroxenites and Websterites
Features
Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel
Generally rough to touch, Host rock for Diamond, Is one of the oldest rock
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Present
Absent
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.
Pyroxenites are ultramafic igneous rocks which are made up of minerals of the pyroxene group, such as augite and diopside, hypersthene, bronzite or enstatite.
Composition
Mineral Content
-
Amphibole, Augite, Bronzite, Chromite, Diopside, Enstatite, Garnet, Hornblende, Hypersthene, Magnetite, Pyroxene
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
Burial Metamorphism, Impact Metamorphism, Regional Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Physical Properties
Hardness
17
1
7
👆🏻
Grain Size
Medium to Fine Coarse Grained
Coarse Grained
Fracture
Conchoidal
Uneven
Streak
Black
White, Greenish White or Grey
Porosity
Highly Porous
Less Porous
Luster
Dull to Vitreous to Submetallic
Dull to Vitreous to Submetallic
Compressive Strength
-150.00 N/mm2
0.15
450
👆🏻
Cleavage
-
-
Toughness
-
-
Specific Gravity
1.1-1.43.2-3.5
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
800-801 g/cm33.1-3.6 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
1.26 kJ/Kg K0.84 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant
Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
India, Russia
Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
South Africa
Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Germany, Greece, Italy, Scotland, Turkey
Others
-
Greenland
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Brazil, Chile, Colombia, Venezuela
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, Queensland, Victoria
New Zealand, Queensland