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
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Origin
Adak, Aleutian Islands
Hawaii Islands
Discoverer
Defant and Drummond
Unknown
Etymology
From Adak, Aleutian Islands
From Greek pikros bitter + -ite, 19th century
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
Fine Grained Rock, Opaque Rock
Texture
Porphyritic
Earthy, Rough
Color
Black, Brown, Light to Dark Grey
Black, Brown, Colourless, Green, Grey, Pink, White, Yellow
Durability
Durable
Durable
Appearance
Dull and Soft
Rough and Shiny
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Hotels, Kitchens
Countertops, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Whetstones
Curbing
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
As a Sintering Agent in Steel Industry to process Iron Ore, Cement Manufacture, for Road Aggregate, Manufacture of Magnesium and Dolomite Refractories, Roadstone, Used for flooring, stair treads, borders and window sills.
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Commemorative Tablets, Pottery, Used in aquariums
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Types
Not Available
Oceanite
Features
Has High structural resistance against erosion and climate, Host rock for Diamond, Very fine grained rock
Host Rock for Lead
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
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.
Picrite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Olivine, Plagioclase, Pyroxene
Biotite, Olivine, Plagioclase, Pyrrhotite
Compound Content
Aluminium Oxide, MgO, Silicon Dioxide
Al, CaO, Carbon Dioxide, Mg, MgO
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Coastal Erosion, Sea Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Fine to Medium Grained
Fine Grained
Fracture
Conchoidal
Uneven
Streak
Bluish Black
White, Greenish White or Grey
Porosity
Less Porous
Less Porous
Luster
Grainy, Pearly and Vitreous
Subvitreous to Dull
Compressive Strength
Not Available
Cleavage
Not Available
Imperfect
Toughness
Not Available
2.1
Specific Gravity
Not Available
2.75-2.92
Transparency
Opaque
Opaque
Density
Not Available
1.5-2.5 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
India, Russia
India, Russia
Africa
Ethiopia, Somalia, South Africa
South Africa
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Brazil
Deposits in Oceania Continent
Australia
Not Yet Found
Not Yet Found
Adakite vs Picrite 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 Picrite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Adakite and Properties of Picrite. Learn more about Adakite vs Picrite in the next section. The interior uses of Adakite include Decorative aggregates, Floor tiles, Homes, Hotels and Kitchens whereas the interior uses of Picrite include Countertops, Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Adakite and Picrite, 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 Picrite include As a sintering agent in steel industry to process iron ore, Cement manufacture, For road aggregate, Manufacture of magnesium and dolomite refractories, Roadstone, Used for flooring, stair treads, borders and window sills..
More about Adakite and Picrite
Here you can know more about Adakite and Picrite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Adakite and Picrite consists of mineral content and compound content. The mineral content of Adakite includes Olivine, Plagioclase, Pyroxene and mineral content of Picrite includes Biotite, Olivine, Plagioclase, Pyrrhotite. You can also check out the list of all Igneous Rocks. When we have to compare Adakite vs Picrite, 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, Picrite is available in black, brown, colourless, green, grey, pink, white, yellow colors. Appearance of Adakite is Dull and Soft and that of Picrite is Rough and Shiny. Properties of rock is another aspect for Adakite vs Picrite. The hardness of Adakite is 3-4 and that of Picrite is 6.8. The types of Adakite are Not Available whereas types of Picrite are Oceanite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Adakite is bluish black while that of Picrite is white, greenish white or grey. The specific heat capacity of Adakite is Not Available and that of Picrite is 0.88 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 Picrite is heat resistant.