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
  
Websterite is ultramafic and ultrabasic rock that consists of roughly equal proportions of orthopyroxene and clinopyroxene. It is a special type of pyroxenite.
  
History
  
  
Origin
New Zealand
  
Webster, North Carolina
  
Discoverer
Unknown
  
Unknown
  
Etymology
From Greek mulōn mill + -ite
  
From the town of Webster located in North Carolina
  
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
  
Coarse Grained Rock, Opaque Rock
  
Texture
Foliated
  
Clastic, Granular, Phaneritic, Porphyritic
  
Color
Black to Grey
  
Black to Grey, Bluish - Grey, Dark Greenish - Grey, Green, Light Greenish Grey
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
No
  
Yes
  
Acid Resistant
No
  
Yes
  
Appearance
Dull, Banded and Foilated
  
Layered, Banded, Veined and Shiny
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Interior Decoration
  
Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
  
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
for Road Aggregate, Landscaping, Roadstone
  
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments
  
Artifacts
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Gemstone, Jewelry
  
Cemetery Markers, Commemorative Tablets, Creating Artwork, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
  
Types
Blastomylonites, Ultramylonites and Phyllonites
  
Not Available
  
Features
Surfaces are often shiny
  
Generally rough to touch, Is one of the oldest rock
  
Archaeological Significance
  
  
Monuments
Used
  
Not Yet Used
  
Famous Monuments
Data Not Available
  
Data Not Available
  
Sculpture
Used
  
Not Yet Used
  
Famous Sculptures
Data Not Available
  
Data Not Available
  
Pictographs
Used
  
Not Used
  
Petroglyphs
Used
  
Not Used
  
Figurines
Used
  
Not Yet Used
  
Fossils
Absent
  
Absent
  
Formation
Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.
  
Websterite can be formed as cumulates in ultramafic intrusions by accumulation of pyroxene crystals at the base of the lava chamber.
  
Composition
  
  
Mineral Content
Porphyroblasts
  
Amphibole, Augite, Bronzite, Chromite, Diopside, Enstatite, Garnet, Hornblende, Hypersthene, Magnetite, Pyroxene
  
Compound Content
Aluminium Oxide, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide
  
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
  
Transformation
  
  
Metamorphism
No
  
Yes
  
Types of Metamorphism
Not Applicable
  
Burial Metamorphism, Impact Metamorphism
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
  
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
3-4
  
7
  
Grain Size
Fine Grained
  
Coarse Grained
  
Fracture
Conchoidal
  
Uneven
  
Streak
White
  
White, Greenish White or Grey
  
Porosity
Highly Porous
  
Less Porous
  
Luster
Shiny
  
Dull to Vitreous to Submetallic
  
Compressive Strength
Not Available
  
Cleavage
Conchoidal
  
Irregular
  
Toughness
Not Available
  
Not Available
  
Specific Gravity
2.97-3.05
  
3.2-3.5
  
Transparency
Opaque
  
Opaque
  
Density
2.6-4.8 g/cm3
  
3.1-3.6 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
1.50 kJ/Kg K
  
3
Not Available
  
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
  
Impact Resistant, Pressure Resistant, Wear Resistant
  
Deposits in Eastern Continents
  
  
Asia
China, India, Indonesia, Saudi Arabia, South Korea
  
India, Russia
  
Africa
Eritrea, Ethiopia, Ghana, South Africa, Western Africa
  
South Africa
  
Europe
England, Finland, France, Germany, Great Britain, Greece, United Kingdom
  
Germany, Greece, Italy, Scotland, Turkey
  
Others
Not Yet Found
  
Greenland
  
Deposits in Western Continents
  
  
North America
USA
  
Canada, USA
  
South America
Not Yet Found
  
Brazil, Colombia, Venezuela
  
Deposits in Oceania Continent
  
  
Australia
Central Australia, Western Australia
  
New Zealand, Queensland
  
All about Mylonite and Websterite Properties
Know all about Mylonite and Websterite properties here. All properties of rocks are important as they define the type of rock and its application. Mylonite belongs to Metamorphic Rocks while Websterite belongs to Igneous Rocks.Texture of Mylonite is Foliated whereas that of Websterite is Clastic, Granular, Phaneritic, Porphyritic. Mylonite appears Dull, Banded and Foilated and Websterite appears Layered, Banded, Veined and Shiny. The luster of Mylonite is shiny while that of Websterite is dull to vitreous to submetallic. Mylonite is available in black to grey colors whereas Websterite is available in black to grey, bluish - grey, dark greenish - grey, green, light greenish grey colors. The commercial uses of Mylonite are creating artwork, gemstone, jewelry and that of Websterite are cemetery markers, commemorative tablets, creating artwork, laboratory bench tops, jewelry, sea defence, tombstones.