Definition
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Granodiorite is a coarse-grained intrusive igneous rock containing quartz and plagioclase, and which has composition in between granite and diorite
Discoverer
Unknown
Unknown
Etymology
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
From granite + diorite
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Porphyritic
Granular, Phaneritic
Color
Blue, Bluish - Grey
Black, Grey, Orange, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Foliated
Veined or Pebbled
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Stair Treads
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, Bridges, Paving Stone, Garden Decoration, Office Buildings, Resorts
Other Architectural Uses
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
As Dimension Stone
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers
Curling, Gemstone, Laboratory bench tops, Tombstones
Types
Rhyolite
Granodiorite
Features
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
Available in Lots of Colors and Patterns
Archaeological Significance
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.
Granodiorite is an intrusive igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks.
Mineral Content
Albite, Amphibole, Quartz
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Al, Fe, Potassium Oxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Chemical Weathering
Types of Erosion
Coastal Erosion, Water Erosion
Chemical Erosion, Glacier Erosion, Wind Erosion
Grain Size
Medium Grained
Medium to Coarse Grained
Streak
Bluish Black
White
Porosity
Highly Porous
Less Porous
Luster
Dull
Grainy, Pearly and Vitreous
Specific Gravity
2.38
2.6-2.7
Transparency
Opaque
Opaque
Density
-9999 g/cm3
2.6-2.8 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
East Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Italy
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic
Deposits in Western Continents
North America
-
Canada, USA
Deposits in Oceania Continent