1 Definition
1.1 Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
1.4 Class
Metamorphic Rocks
Igneous 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, Pink, White
Black, Brown, Colourless, Green, Grey, Red, Rust, 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, Entryways, Interior Decoration
Decorative Aggregates, Interior Decoration
3.1.2 Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
Garden Decoration, Paving Stone
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
Construction Aggregate
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts, Monuments
Artifacts, Monuments, Sculpture
3.4 Other Uses
3.4.1 Commercial Uses
Creating Artwork, Gemstone
Creating Artwork, Gemstone, Jewelry
4 Types
4.1 Types
Not Available
Rhomb Porphyry
4.2 Features
Host Rock for Lead
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
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
Not Applicable
Data Not Available
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 Formation
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.
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.
5.2 Composition
5.2.1 Mineral Content
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
5.2.2 Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
5.3.3 Weathering
5.3.4 Types of Weathering
Not Applicable
Biological Weathering, Chemical Weathering, Not Registered
5.3.5 Erosion
5.3.6 Types of Erosion
Not Applicable
Chemical Erosion, Coastal Erosion, Glacier Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Very fine-grained
Fine Grained
6.1.3 Fracture
6.1.4 Streak
Light to dark brown
White
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
Transparent to Translucent
Translucent to Opaque
6.1.12 Density
2.7-2.9 g/cm32.5-2.52 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant
Heat Resistant, Impact Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
South Korea
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
7.1.2 Africa
Western Africa
Egypt, Ethiopia, Ghana, South Africa
7.1.3 Europe
Great Britain, Switzerland
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
7.1.4 Others
7.2 Deposits in Western Continents
7.2.1 North America
Not Yet Found
Canada, Cuba, Jamaica, USA
7.2.2 South America
Not Yet Found
Bolivia, Brazil, Colombia, Ecuador, Paraguay
7.3 Deposits in Oceania Continent
7.3.1 Australia
Central Australia, Western Australia
New South Wales, New Zealand, Western Australia