Definition
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Sandstone is defined as a rock which is composed of sand-sized grains of various minerals mostly of uniform size and often are smooth and rounded
History
Origin
Italy
-
Discoverer
Unknown
Unknown
Etymology
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
From its composition, sand and stone
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
-
Other Categories
Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Texture
Porphyritic
Clastic, Granular, Rough
Color
Blue, Bluish - Grey
Beige, Black, Brown, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Maintenance
Less
More
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Foliated
Rough
Architecture
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar
Cement Manufacture, Construction Aggregate, for Road Aggregate, Production of Glass and Ceramics, Raw material for the manufacture of mortar
Medical Industry
-
-
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Other Uses
Commercial Uses
Cemetery Markers
An Oil and Gas Reservoir, In aquifers, Petroleum reservoirs, Soil Conditioner, Source of Magnesia (MgO), Tombstones, Used in aquariums
Types
Rhyolite
Grey Sandstones, Crystallized Sandstones, Hard Sandstones , Carbonate Cemented Sandstones and Ganister
Features
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
Available in Lots of Colors and Patterns, Generally rough to touch, Very fine grained rock
Archaeological Significance
Monuments
-
-
Famous Monuments
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Abu Simbel in Egypt, Agia Sophia in Istanbul, Turkey, Angkor Wat in Cambodia, Buland Darwaza in Agra, India, Chhatrapati Shivaji Terminus in Maharashtra, India, Dom in Berlin, Great Sphinx at Giza, Egypt, Hawa Mahal in Jaipur, India, Humayun's Tomb in Delhi, India, India Gate in Delhi, India, Jama Masjid in Delhi, India, Khajuraho Temples, India, Leh Palace in Leh, India, Lotus Temple in New Delhi, India, Luxor Temple in Egypt, Machu Picchu in Peru, Neuschwanstein in Bavaria, Petra in Jordan, Qutb Minar in India, Red Fort in Delhi, India, Sanchi Stupa in India
Sculpture
-
-
Famous Sculptures
-
Ajanta Caves in Maharashtra, India, Elephanta Caves in Maharashtra, India, Mount Rushmore National Memorial in South Dakota, US
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
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.
Sandstone is a sedimentary rock which forms from cemented sand-sized clasts. It forms when sand layers are buried under sediments of sand.
Composition
Mineral Content
Albite, Amphibole, Quartz
Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz
Compound Content
Al, Fe, Potassium Oxide
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Cataclastic Metamorphism, Regional Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Coastal Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
6-76-7
1
7
👆🏻
Grain Size
Medium Grained
Coarse or Fine
Fracture
Pervasive
Conchoidal
Streak
Bluish Black
White
Porosity
Highly Porous
Highly Porous
Luster
Dull
Dull
Compressive Strength
92.40 N/mm295.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Perfect
Toughness
2
2.6
Specific Gravity
2.382.2-2.8
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
-9999 g/cm32.2-2.8 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.79 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China
China, India, Kazakhstan, Mongolia, Russia, Thailand, Uzbekistan
Africa
East Africa
Namibia, Nigeria, South Africa
Europe
Italy
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Others
-
Greenland
Deposits in Western Continents
North America
-
Canada, USA
South America
-
Brazil
Deposits in Oceania Continent
Australia
Queensland
New South Wales, New Zealand