Definition
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Gritstone or grit is a hard, coarse-grained, siliceous sandstone
Origin
Italy
Pennines, England
Discoverer
Unknown
J.J. Ferber
Etymology
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
From Grit + Stone
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Group
Volcanic
Not Applicable
Other Categories
Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Porphyritic
Earthy
Color
Blue, Bluish - Grey
Beige, Black, Brown, Colourless, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Foliated
Layered and Foliated
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar
Construction Aggregate, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO), Tombstones
Types
Rhyolite
Not Available
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
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Figurines
Not Yet Used
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.
Gritstone is a type of sedimentary rock which was formed on the floors of wide river deltas where the grit deposits were laid down, with every tide or flood dumping another layer of sediment.
Mineral Content
Albite, Amphibole, Quartz
Calcite, Clay Minerals, Feldspar, Micas, Quartz
Compound Content
Al, Fe, Potassium Oxide
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
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, Coastal Erosion
Grain Size
Medium Grained
Coarse Grained
Fracture
Pervasive
Conchoidal
Streak
Bluish Black
White
Porosity
Highly Porous
Highly Porous
Cleavage
Not Available
Perfect
Toughness
2
Not Available
Specific Gravity
2.38
2.250
Transparency
Opaque
Opaque
Density
Not Available
2.2 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
East Africa
Namibia, Nigeria, South Africa
Europe
Italy
Austria, Denmark, Germany, Great Britain, Netherlands, Poland, Sweden, Switzerland, United Kingdom
Others
Not Yet Found
Greenland
Deposits in Western Continents
North America
Not Yet Found
Canada, USA
South America
Not Yet Found
Brazil
Deposits in Oceania Continent
Australia
Queensland
New South Wales, New Zealand, Western Australia
All about Comendite and Gritstone Properties
Know all about Comendite and Gritstone properties here. All properties of rocks are important as they define the type of rock and its application. Comendite belongs to Igneous Rocks while Gritstone belongs to Sedimentary Rocks.Texture of Comendite is Porphyritic whereas that of Gritstone is Earthy. Comendite appears Foliated and Gritstone appears Layered and Foliated. The luster of Comendite and Gritstone is dull. Comendite is available in blue, bluish - grey colors whereas Gritstone is available in beige, black, brown, colourless, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors. The commercial uses of Comendite are cemetery markers and that of Gritstone are an oil and gas reservoir, as a feed additive for livestock, gemstone, metallurgical flux, production of lime, soil conditioner, source of magnesia (mgo), tombstones.