Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Discoverer
Unknown
Unknown
Etymology
From French, Latin lignum wood + -ite1
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Group
Not Applicable
Volcanic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Medium Grained Rock, Opaque Rock
Texture
Amorphous, Glassy
Porphyritic
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Blue, Bluish - Grey
Durability
Durable
Durable
Appearance
Veined or Pebbled
Foliated
Interior Uses
Not Yet Used
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
Not Yet Used
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
Not Yet Used
Curbing
Construction Industry
for Road Aggregate, Steel Production
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Not Yet Used
Artifacts
Commercial Uses
Electricity Generation
Cemetery Markers
Types
Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite
Rhyolite
Features
Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
Archaeological Significance
Monuments
Not Yet Used
Not Yet Used
Famous Monuments
Not Applicable
Not Applicable
Sculpture
Not Yet Used
Not Yet Used
Famous Sculptures
Not Applicable
Not Applicable
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Figurines
Not Yet Used
Not Yet Used
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.
Comendite is a type of Igneous rock which is formed due to cooling and solidification of lava or magma. It may form with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Not Available
Albite, Amphibole, Quartz
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Al, Fe, Potassium Oxide
Types of Metamorphism
Not Applicable
Cataclastic Metamorphism, Regional 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
Coastal Erosion, Water Erosion
Grain Size
Medium to Fine Coarse Grained
Medium Grained
Fracture
Conchoidal
Pervasive
Streak
Black
Bluish Black
Porosity
Highly Porous
Highly Porous
Luster
Dull to Vitreous to Submetallic
Dull
Compressive Strength
Not Available
Cleavage
Non-Existent
Not Available
Toughness
Not Available
2
Specific Gravity
1.1-1.4
2.38
Transparency
Opaque
Opaque
Density
800-801 g/cm3
Not Available
Specific Heat Capacity
Not Available
Resistance
Heat Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
China
Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
East Africa
Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Italy
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, Mexico, USA
Not Yet Found
South America
Brazil, Chile, Colombia, Venezuela
Not Yet Found
Deposits in Oceania Continent
Australia
New South Wales, Queensland, Victoria
Queensland