Home
Compare Rocks


Porphyry and Basalt


Basalt and Porphyry


Definition

Definition
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix   
Basalt is a common extrusive igneous rock formed by the rapid cooling of basaltic lava exposed at or very near the surface of Earth   

History
  
  

Origin
Egypt   
Egypt   

Discoverer
Unknown   
Georgius Agricola   

Etymology
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites   
From Late Latin Basaltes (variant of basanites ), very hard stone, which was imported from Ancient Greek Basanites   

Class
Igneous Rocks   
Igneous Rocks   

Sub-Class
Durable Rock, Hard Rock   
Durable Rock, Medium Hardness Rock   

Family
  
  

Group
Plutonic   
Volcanic   

Other Categories
Fine Grained Rock, Opaque Rock   
Fine Grained Rock, Opaque Rock   

Texture

Texture
Porphyritic   
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular   

Color
Black, Brown, Colourless, Green, Grey, Red, Rust, White   
Black, Brown, Light to Dark Grey   

Maintenance
Less   
More   

Durability
Durable   
Durable   

Water Resistant
No   
No   

Scratch Resistant
Yes   
Yes   

Stain Resistant
Yes   
Yes   

Wind Resistant
No   
No   

Acid Resistant
Yes   
Yes   

Appearance
Dull   
Dull and Soft   

Uses

Architecture
  
  

Interior Uses
Decorative Aggregates, Interior Decoration   
Floor Tiles, Homes, Hotels, Kitchens   

Exterior Uses
Garden Decoration, Paving Stone   
As Building Stone, Paving Stone, Garden Decoration, Office Buildings   

Other Architectural Uses
Curbing   
Curbing, Whetstones   

Industry
  
  

Construction Industry
Construction Aggregate   
Arrowheads, As Dimension Stone, Cobblestones, Cutting Tool, Rail Track Ballast, Roadstone   

Medical Industry
Not Yet Used   
Not Yet Used   

Antiquity Uses
Artifacts, Monuments, Sculpture   
Artifacts, Monuments   

Other Uses
  
  

Commercial Uses
Creating Artwork, Gemstone, Jewelry   
An Oil and Gas Reservoir, Commemorative Tablets, Creating Artwork, Used in aquariums   

Types

Types
Rhomb Porphyry   
Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite   

Features
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny   
Has High structural resistance against erosion and climate, Very fine grained rock   

Archaeological Significance
  
  

Monuments
Used   
Used   

Famous Monuments
Data Not Available   
Easter Island in the Polynesian Triangle, Pacific Ocean, Gateway of India in Mumbai, India, Gol Gumbaz in Karnataka, India   

Sculpture
Used   
Used   

Famous Sculptures
Data Not Available   
Data Not Available   

Pictographs
Not Used   
Used   

Petroglyphs
Not Used   
Used   

Figurines
Used   
Used   

Fossils
Absent   
Absent   

Formation

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.   
Basalt forms when lava reaches the Earth's surface near an active volcano. The temperature of lava is between 1100 to 1250° C when it gets to the surface.   

Composition
  
  

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, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide   

Transformation
  
  

Metamorphism
Yes   
Yes   

Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism   
Contact Metamorphism   

Weathering
Yes   
Yes   

Types of Weathering
Biological Weathering, Chemical Weathering, Not Registered   
Biological Weathering   

Erosion
Yes   
No   

Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion   
Not Available   

Properties

Physical Properties
  
  

Hardness
6-7   
6   

Grain Size
Fine Grained   
Fine Grained   

Fracture
Irregular   
Conchoidal   

Streak
White   
White to Grey   

Porosity
Less Porous   
Less Porous   

Luster
Dull   
Not Available   

Compressive Strength
Not Available   
37.40 N/mm2   
28

Cleavage
Imperfect   
Not Available   

Toughness
1.7   
2.3   

Specific Gravity
2.5-4   
2.8-3   

Transparency
Translucent to Opaque   
Opaque   

Density
2.5-2.52 g/cm3   
2.9-3.1 g/cm3   

Thermal Properties
  
  

Specific Heat Capacity
Not Available   
0.84 kJ/Kg K   
15

Resistance
Heat Resistant, Impact Resistant   
Heat Resistant, Pressure Resistant, Wear Resistant   

Reserves

Deposits in Eastern Continents
  
  

Asia
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam   
India, Russia   

Africa
Egypt, Ethiopia, Ghana, South Africa   
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   

Summary >>
<< Reserves

All about Porphyry and Basalt Properties

Know all about Porphyry and Basalt properties here. All properties of rocks are important as they define the type of rock and its application. Porphyry and Basalt belong to Igneous Rocks.Texture of Porphyry is Porphyritic whereas that of Basalt is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular. Porphyry appears Dull and Basalt appears Dull and Soft. The luster of Porphyry is dull while that of Basalt is not available. Porphyry is available in black, brown, colourless, green, grey, red, rust, white colors whereas Basalt is available in black, brown, light to dark grey colors. The commercial uses of Porphyry are creating artwork, gemstone, jewelry and that of Basalt are an oil and gas reservoir, commemorative tablets, creating artwork, used in aquariums.

Compare Igneous Rocks

Igneous Rocks

Igneous Rocks

» More Igneous Rocks

Compare Igneous Rocks

» More Compare Igneous Rocks