Definition
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
Pegmatite rock is a holocrystalline, intrusive igneous rock which is composed of interlocking phaneritic crystals
Discoverer
Unknown
R. J. Hauy
Etymology
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
From Greek pegma, pegmat which means- thing joined together + -ite
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Porphyritic
Pegmatitic
Color
Black, Brown, Colourless, Green, Grey, Red, Rust, White
Black, Brown, Cream, Green, Grey, Pink, Red, Rust, Silver, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
Construction Aggregate
As Dimension Stone, Building houses or walls, Construction Aggregate, for Road Aggregate, Landscaping
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Gemstone, Jewelry
Creating Artwork, Jewelry, Source of corundum, tourmalines, beryls and topaz
Types
Rhomb Porphyry
Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite
Features
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Generally rough to touch, Is one of the oldest rock, Source of corundum, tourmalines, beryls and topaz
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not 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.
Pegmatite rock is holocrystalline, intrusive igneous rock which is formed by partial melting and dewatering during the process of metamorphism.
Mineral Content
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, Phosphorus Pentoxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Not Registered
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Medium to Coarse Grained
Fracture
Irregular
Conchoidal
Porosity
Less Porous
Less Porous
Luster
Dull
Grainy, Pearly and Vitreous
Compressive Strength
Not Available
Cleavage
Imperfect
Perfect
Specific Gravity
2.5-4
2.6-2.63
Transparency
Translucent to Opaque
Translucent to Opaque
Density
2.5-2.52 g/cm3
2.6-2.65 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
China, India, Iran, Japan, Nepal, North Korea, Russia, Saudi Arabia, South Korea
Africa
Egypt, Ethiopia, Ghana, South Africa
South Africa
Europe
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
Austria, France, Greece, Ireland, Italy, Netherlands, Slovakia, Spain, Turkey, Ukraine
Others
Greenland
Not Yet Found
Deposits in Western Continents
North America
Canada, Cuba, Jamaica, USA
Canada
South America
Bolivia, Brazil, Colombia, Ecuador, Paraguay
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Western Australia
New South Wales, Queensland, South Australia, Western Australia
Porphyry vs Pegmatite 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 Pegmatite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Porphyry and Properties of Pegmatite. Learn more about Porphyry vs Pegmatite in the next section. The interior uses of Porphyry include Decorative aggregates and Interior decoration whereas the interior uses of Pegmatite include Decorative aggregates, Flooring and Interior decoration. Due to some exceptional properties of Porphyry and Pegmatite, they have various applications in construction industry. The uses of Porphyry in construction industry include Construction aggregate and that of Pegmatite include As dimension stone, Building houses or walls, Construction aggregate, For road aggregate, Landscaping.
More about Porphyry and Pegmatite
Here you can know more about Porphyry and Pegmatite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Porphyry and Pegmatite consists of mineral content and compound content. The mineral content of Porphyry includes Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica and mineral content of Pegmatite includes Apatite, Beryl, Feldspar, Fluorite, Garnet, Lepidolite, Quartz, Silica, Spodumene, Topaz. You can also check out the list of all . When we have to compare Porphyry vs Pegmatite, 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, Pegmatite is available in black, brown, cream, green, grey, pink, red, rust, silver, white, yellow colors. Appearance of Porphyry is Dull and that of Pegmatite is Layered, Banded, Veined and Shiny. Properties of rock is another aspect for Porphyry vs Pegmatite. The hardness of Porphyry is 6-7 and that of Pegmatite is 7. The types of Porphyry are Rhomb Porphyry whereas types of Pegmatite are Granite Pegmatite, Gabbro Pegmatite and Diorite Pegmatite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Porphyry and Pegmatite is white. The specific heat capacity of Porphyry is Not Available and that of Pegmatite 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 Pegmatite is heat resistant, impact resistant, pressure resistant.