Definition
Adakite is an intermediate to felsic volcanic rock that has geochemical characteristics of magma which is said to be formed by partial melting of altered basalt that is subducted below volcanic arcs
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Origin
Adak, Aleutian Islands
Italy
Discoverer
Defant and Drummond
Unknown
Etymology
From Adak, Aleutian Islands
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Medium Grained Rock, Opaque Rock
Texture
Porphyritic
Porphyritic
Color
Black, Brown, Light to Dark Grey
Blue, Bluish - Grey
Durability
Durable
Durable
Appearance
Dull and Soft
Foliated
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Hotels, Kitchens
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
Whetstones
Curbing
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
Monuments, Sculpture, Small Figurines
Artifacts
Commercial Uses
Commemorative Tablets, Pottery, Used in aquariums
Cemetery Markers
Types
Intermediate volcanic rock
Rhyolite
Features
Has High structural resistance against erosion and climate, Host rock for Diamond, Very fine grained rock
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
Archaeological Significance
Formation
Adakite rocks are formed when the hydrous fluids are released from minerals that break down in metamorphosed basalt, and rise into the mantle they initiate partial melting.
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.
Mineral Content
Olivine, Plagioclase, Pyroxene
Albite, Amphibole, Quartz
Compound Content
Aluminium Oxide, MgO, Silicon Dioxide
Al, Fe, Potassium Oxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Regional Metamorphism
Types of Weathering
Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Sea Erosion, Water Erosion
Coastal Erosion, Water Erosion
Grain Size
Fine to Medium Grained
Medium Grained
Fracture
Conchoidal
Pervasive
Streak
Bluish Black
Bluish Black
Porosity
Less Porous
Highly Porous
Luster
Grainy, Pearly and Vitreous
Dull
Specific Gravity
-9999
2.38
Transparency
Opaque
Opaque
Density
-9999 g/cm3
-9999 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Africa
Ethiopia, Somalia, South Africa
East Africa
Deposits in Western Continents
North America
Canada, USA
-
Deposits in Oceania Continent
Adakite vs Comendite Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Adakite vs Comendite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Adakite and Properties of Comendite. Learn more about Adakite vs Comendite in the next section. The interior uses of Adakite include Decorative aggregates, Floor tiles, Homes, Hotels and Kitchens whereas the interior uses of Comendite include Countertops, Decorative aggregates and Interior decoration. Due to some exceptional properties of Adakite and Comendite, they have various applications in construction industry. The uses of Adakite in construction industry include As dimension stone, Cobblestones, Rail track ballast, Roadstone and that of Comendite include Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar.
More about Adakite and Comendite
Here you can know more about Adakite and Comendite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Adakite and Comendite consists of mineral content and compound content. The mineral content of Adakite includes Olivine, Plagioclase, Pyroxene and mineral content of Comendite includes Albite, Amphibole, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Adakite vs Comendite, the texture, color and appearance plays an important role in determining the type of rock. Adakite is available in black, brown, light to dark grey colors whereas, Comendite is available in blue, bluish - grey colors. Appearance of Adakite is Dull and Soft and that of Comendite is Foliated. Properties of rock is another aspect for Adakite vs Comendite. The hardness of Adakite is 3-4 and that of Comendite is 6-7. The types of Adakite are Intermediate volcanic rock whereas types of Comendite are Rhyolite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Adakite and Comendite is bluish black. The specific heat capacity of Adakite is 0.84 kJ/Kg K and that of Comendite is 0.79 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Adakite is heat resistant, pressure resistant, wear resistant whereas Comendite is heat resistant, impact resistant.