Definition
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
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
Origin
Egypt
Adak, Aleutian Islands
Discoverer
Unknown
Defant and Drummond
Etymology
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
From Adak, Aleutian Islands
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Porphyritic
Porphyritic
Color
Black, Brown, Colourless, Green, Grey, Red, Rust, White
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Appearance
Dull
Dull and Soft
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Floor Tiles, Homes, Hotels, Kitchens
Exterior Uses
Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
Curbing
Whetstones
Construction Industry
Construction Aggregate
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Gemstone, Jewelry
Commemorative Tablets, Pottery, Used in aquariums
Types
Rhomb Porphyry
Not Available
Features
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Has High structural resistance against erosion and climate, Host rock for Diamond, Very fine grained rock
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Formation
Porphyry is formed in two stages: the magma cools slowly deep within the crust or the magma is cools rapidly as it erupts from a volcano, creating small grains that are usually invisible to naked eye.
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.
Mineral Content
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
Olivine, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, MgO, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Not Registered
Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Coastal Erosion, Sea Erosion, Water Erosion
Grain Size
Fine Grained
Fine to Medium Grained
Fracture
Irregular
Conchoidal
Streak
White
Bluish Black
Porosity
Less Porous
Less Porous
Luster
Dull
Grainy, Pearly and Vitreous
Cleavage
Imperfect
Not Available
Toughness
1.7
Not Available
Specific Gravity
2.5-4
Not Available
Transparency
Translucent to Opaque
Opaque
Density
2.5-2.52 g/cm3
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
India, Russia
Africa
Egypt, Ethiopia, Ghana, South Africa
Ethiopia, Somalia, South Africa
Europe
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
Iceland
Others
Greenland
Not Yet Found
Deposits in Western Continents
North America
Canada, Cuba, Jamaica, USA
Canada, USA
South America
Bolivia, Brazil, Colombia, Ecuador, Paraguay
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Western Australia
Not Yet Found
Porphyry vs Adakite 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. Porphyry vs Adakite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Porphyry and Properties of Adakite. Learn more about Porphyry vs Adakite in the next section. The interior uses of Porphyry include Decorative aggregates and Interior decoration whereas the interior uses of Adakite include Decorative aggregates, Floor tiles, Homes, Hotels and Kitchens. Due to some exceptional properties of Porphyry and Adakite, they have various applications in construction industry. The uses of Porphyry in construction industry include Construction aggregate and that of Adakite include As dimension stone, Cobblestones, Rail track ballast, Roadstone.
More about Porphyry and Adakite
Here you can know more about Porphyry and Adakite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Porphyry and Adakite consists of mineral content and compound content. The mineral content of Porphyry includes Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica and mineral content of Adakite includes Olivine, Plagioclase, Pyroxene. You can also check out the list of all Igneous Rocks. When we have to compare Porphyry vs Adakite, the texture, color and appearance plays an important role in determining the type of rock. Porphyry is available in black, brown, colourless, green, grey, red, rust, white colors whereas, Adakite is available in black, brown, light to dark grey colors. Appearance of Porphyry is Dull and that of Adakite is Dull and Soft. Properties of rock is another aspect for Porphyry vs Adakite. The hardness of Porphyry is 6-7 and that of Adakite is 3-4. The types of Porphyry are Rhomb Porphyry whereas types of Adakite are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Porphyry is white while that of Adakite is bluish black. The specific heat capacity of Porphyry is Not Available and that of Adakite is Not Available. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Porphyry is heat resistant, impact resistant whereas Adakite is heat resistant, pressure resistant, wear resistant.