Definition
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Discoverer
Unknown
Unknown
Etymology
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
From French, Latin lignum wood + -ite1
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
Group
Volcanic
Not Applicable
Other Categories
Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Porphyritic
Amorphous, Glassy
Color
Blue, Bluish - Grey
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Durability
Durable
Durable
Appearance
Foliated
Veined or Pebbled
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Not Yet Used
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
Not Yet Used
Other Architectural Uses
Curbing
Not Yet Used
Construction Industry
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar
for Road Aggregate, Steel Production
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Not Yet Used
Commercial Uses
Cemetery Markers
Electricity Generation
Types
Rhyolite
Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite
Features
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel
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
Not Used
Used
Petroglyphs
Not Used
Used
Figurines
Not Yet Used
Not Yet Used
Formation
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.
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.
Mineral Content
Albite, Amphibole, Quartz
Not Available
Compound Content
Al, Fe, Potassium Oxide
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Types of Metamorphism
Cataclastic Metamorphism, Regional Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Water Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Medium Grained
Medium to Fine Coarse Grained
Fracture
Pervasive
Conchoidal
Streak
Bluish Black
Black
Porosity
Highly Porous
Highly Porous
Luster
Dull
Dull to Vitreous to Submetallic
Compressive Strength
Not Available
Cleavage
Not Available
Non-Existent
Toughness
2
Not Available
Specific Gravity
2.38
1.1-1.4
Transparency
Opaque
Opaque
Density
Not Available
800-801 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
Africa
East Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Europe
Italy
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Not Yet Found
Canada, Mexico, USA
South America
Not Yet Found
Brazil, Chile, Colombia, Venezuela
Deposits in Oceania Continent
Australia
Queensland
New South Wales, Queensland, Victoria