1 Definition
1.1 Definition
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
1.4 Class
Igneous Rocks
Metamorphic Rocks
1.4.1 Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
2 Texture
2.1 Texture
2.2 Color
Black, Brown, Colourless, Green, Grey, Red, Rust, White
Black, Brown, Colourless, Green, Grey, Pink, White
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
3.1.2 Exterior Uses
Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
Construction Aggregate
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments
3.4 Other Uses
3.4.1 Commercial Uses
Creating Artwork, Gemstone, Jewelry
Creating Artwork, Gemstone
4 Types
4.1 Types
Rhomb Porphyry
Not Available
4.2 Features
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Host Rock for Lead
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Data Not Available
Data Not Available
4.3.3 Sculpture
4.3.4 Famous Sculptures
Data Not Available
Not Applicable
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 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.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Pseudotachylite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
5.2 Composition
5.2.1 Mineral Content
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
5.2.2 Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering, Chemical Weathering, Not Registered
Not Applicable
5.3.5 Erosion
5.3.6 Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Not Applicable
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Fine Grained
Very fine-grained
6.1.3 Fracture
6.1.4 Streak
White
Light to dark brown
6.1.5 Porosity
6.1.6 Luster
6.1.7 Compressive Strength
6.1.8 Cleavage
6.1.9 Toughness
6.1.10 Specific Gravity
6.1.11 Transparency
Translucent to Opaque
Transparent to Translucent
6.1.12 Density
2.5-2.52 g/cm32.7-2.9 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant, Impact Resistant
Heat Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
South Korea
7.1.2 Africa
Egypt, Ethiopia, Ghana, South Africa
Western Africa
7.1.3 Europe
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
Great Britain, Switzerland
7.1.4 Others
7.2 Deposits in Western Continents
7.2.1 North America
Canada, Cuba, Jamaica, USA
Not Yet Found
7.2.2 South America
Bolivia, Brazil, Colombia, Ecuador, Paraguay
Not Yet Found
7.3 Deposits in Oceania Continent
7.3.1 Australia
New South Wales, New Zealand, Western Australia
Central Australia, Western Australia