Definition
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Granulite is fine to medium grained metamorphic rock with a granular of polygonal crystals.
Origin
Italy
Central Europe
Discoverer
Unknown
Unknown
Etymology
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
From Latin granulum, a little grain or fine grained
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Porphyritic
Granoblastic
Color
Blue, Bluish - Grey
Black, Brown
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Foliated
Veined or Pebbled
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Bathrooms, Countertops, Decorative Aggregates, Entryways, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing 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
As Dimension Stone, Building houses or walls
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers
Curling, Gemstone, Laboratory bench tops, Soil Conditioner, Tombstones
Types
Rhyolite
Metamorphic rock
Features
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
Clasts are smooth to touch
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.
Granulite is a fine-grained granular metamorphic rock in which the main component minerals are feldspars and quartz and forms at high temperature and pressure conditions.
Mineral Content
Albite, Amphibole, Quartz
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Quartz
Compound Content
Al, Fe, Potassium Oxide
Aluminium Oxide, CaO, Carbon Dioxide, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Sulfur Dioxide, Titanium Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Regional Metamorphism
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Coastal Erosion, Water Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Medium Grained
Medium to Coarse Grained
Streak
Bluish Black
White
Porosity
Highly Porous
Very Less Porous
Specific Gravity
2.38
2.8-3.0
Transparency
Opaque
Opaque
Density
-9999 g/cm3
3.06-3.33 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, 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