Mylonite and Porphyry
Definition
Definition
Mylonite is a metamorphic rock formed by ductile deformation during intense shearing encountered during folding and faulting, a process termed cataclastic or dynamic metamorphism
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
History
Origin
New Zealand
Egypt
Discoverer
Unknown
Unknown
Etymology
From Greek mulōn mill + -ite
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Family
Group
Not Applicable
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Texture
Foliated
Porphyritic
Color
Black to Grey
Black, Brown, Colourless, Green, Grey, Red, Rust, White
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
Yes
No
Scratch Resistant
Yes
Yes
Stain Resistant
No
Yes
Wind Resistant
No
No
Acid Resistant
No
Yes
Appearance
Dull, Banded and Foilated
Dull
Uses
Architecture
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
for Road Aggregate, Landscaping, Roadstone
Construction Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments
Artifacts, Monuments, Sculpture
Other Uses
Commercial Uses
Creating Artwork, Gemstone, Jewelry
Creating Artwork, Gemstone, Jewelry
Types
Types
Blastomylonites, Ultramylonites and Phyllonites
Rhomb Porphyry
Features
Surfaces are often shiny
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Archaeological Significance
Monuments
Used
Used
Famous Monuments
Data Not Available
Data Not Available
Sculpture
Used
Used
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Figurines
Used
Used
Fossils
Absent
Absent
Formation
Formation
Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.
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.
Composition
Mineral Content
Porphyroblasts
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
Compound Content
Aluminium Oxide, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Transformation
Metamorphism
No
Yes
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Weathering
Yes
Yes
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Not Registered
Erosion
Yes
Yes
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Properties
Physical Properties
Hardness
3-4
6-7
Grain Size
Fine Grained
Fine Grained
Fracture
Conchoidal
Irregular
Streak
White
White
Porosity
Highly Porous
Less Porous
Luster
Shiny
Dull
Compressive Strength
1.28 N/mm2
32
Not Available
Cleavage
Conchoidal
Imperfect
Toughness
Not Available
1.7
Specific Gravity
2.97-3.05
2.5-4
Transparency
Opaque
Translucent to Opaque
Density
2.6-4.8 g/cm3
2.5-2.52 g/cm3
Thermal Properties
Specific Heat Capacity
1.50 kJ/Kg K
3
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant
Reserves
Deposits in Eastern Continents
Asia
China, India, Indonesia, Saudi Arabia, South Korea
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
Africa
Eritrea, Ethiopia, Ghana, South Africa, Western Africa
Egypt, Ethiopia, Ghana, South Africa
Europe
England, Finland, France, Germany, Great Britain, Greece, United Kingdom
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
Others
Not Yet Found
Greenland
Deposits in Western Continents
North America
USA
Canada, Cuba, Jamaica, USA
South America
Not Yet Found
Bolivia, Brazil, Colombia, Ecuador, Paraguay
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New South Wales, New Zealand, Western Australia
All about Mylonite and Porphyry Properties
Know all about Mylonite and Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Mylonite belongs to Metamorphic Rocks while Porphyry belongs to Igneous Rocks.Texture of Mylonite is Foliated whereas that of Porphyry is Porphyritic. Mylonite appears Dull, Banded and Foilated and Porphyry appears Dull. The luster of Mylonite is shiny while that of Porphyry is dull. Mylonite is available in black to grey colors whereas Porphyry is available in black, brown, colourless, green, grey, red, rust, white colors. The commercial uses of Mylonite and Porphyry are creating artwork, gemstone, jewelry.
|
||
|
||
|
