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
Schist is a medium grade metamorphic rock with medium to large, flat, sheet like grains in a preferred orientation
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 French schiste, Greek skhistos i.e. split
1.4 Class
Igneous Rocks
Metamorphic Rocks
1.4.1 Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
2 Texture
2.1 Texture
Porphyritic
Foliated, Platy
2.2 Color
Black, Brown, Colourless, Green, Grey, Red, Rust, White
Black, Blue, Brown, Dark Brown, Green, Grey, Silver
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, Floor Tiles, Interior Decoration
3.1.2 Exterior Uses
Garden Decoration, Paving Stone
Garden Decoration, Paving Stone
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
Construction Aggregate
As Dimension Stone, Building houses or walls, Cement Manufacture, for Road Aggregate, Roadstone
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts
3.4 Other Uses
3.4.1 Commercial Uses
Creating Artwork, Gemstone, Jewelry
Used in aquariums, Writing Slates
4 Types
4.1 Types
Rhomb Porphyry
Mica Schists, Calc-Silicate Schists, Graphite Schists, Blueschists, Whiteschists, Greenschists, Hornblende Schist, Talc Schist, Chlorite Schist, Garnet Schist, Glaucophane schist.
4.2 Features
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Easily splits into thin plates, Smooth to touch
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Data Not Available
Not Applicable
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.
Schist formed by dynamic metamorphism at high temperatures and pressures that aligns the grains of mica, hornblende and other elongated minerals into thin layers.
5.2 Composition
5.2.1 Mineral Content
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
Alusite, Amphibole, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc
5.2.2 Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
CaO, Carbon Dioxide, MgO
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
Not Applicable
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering, Chemical Weathering, Not Registered
Biological Weathering, Chemical Weathering, Mechanical Weathering
5.3.5 Erosion
5.3.6 Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Fine Grained
Medium to Fine Coarse Grained
6.1.3 Fracture
6.1.4 Streak
6.1.5 Porosity
Less Porous
Highly Porous
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
Opaque
6.1.12 Density
2.5-2.52 g/cm32.8-2.9 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant, Impact Resistant
Impact Resistant, Pressure Resistant, Water Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
7.1.2 Africa
Egypt, Ethiopia, Ghana, South Africa
Egypt, Ethiopia, Morocco, Nigeria, South Africa
7.1.3 Europe
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
7.1.4 Others
7.2 Deposits in Western Continents
7.2.1 North America
Canada, Cuba, Jamaica, USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
7.2.2 South America
Bolivia, Brazil, Colombia, Ecuador, Paraguay
Brazil, Colombia, Guyana
7.3 Deposits in Oceania Continent
7.3.1 Australia
New South Wales, New Zealand, Western Australia
New South Wales, New Zealand, Queensland