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
Peridotite is a dense, coarse-grained plutonic is the main constituent of the earth's mantle
Origin
New Zealand
Pike County, U.S
Discoverer
Unknown
Unknown
Etymology
From Greek mulōn mill + -ite
From French, from peridot + -ite
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Foliated
Phaneritic
Color
Black to Grey
Dark Greenish - Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull, Banded and Foilated
Rough and Shiny
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
for Road Aggregate, Landscaping, Roadstone
As Dimension Stone, Cobblestones
Antiquity Uses
Artifacts, Monuments
Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Gemstone, Jewelry
Creating Artwork, Gemstone, Jewelry, Source of Chromite, Platinum, Nickel and Garnet, Source of Diamonds
Types
Blastomylonites, Ultramylonites and Phyllonites
Dunite, Wehrlite, Harzburgite, Lherzolite and Pyrolite
Features
Surfaces are often shiny
Constitutes upper part of the Earth's mantle, Generally rough to touch, Host rock for Diamond, Is one of the oldest rock
Archaeological Significance
Formation
Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.
Peridotites can be formed in two ways: as mantle rocks formed during the accretion and differentiation of the Earth or as cumulate rocks formed by precipitation of olivine and pyroxenes from basaltic magmas.
Mineral Content
Porphyroblasts
Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide
Ca, Fe, Mg, Potassium, Silicon Dioxide, Sodium, Titanium Dioxide
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Chemical Erosion
Grain Size
Fine Grained
Coarse Grained
Fracture
Conchoidal
Irregular
Porosity
Highly Porous
Less Porous
Specific Gravity
2.97-3.05
3-3.01
Transparency
Opaque
Translucent to Opaque
Density
2.6-4.8 g/cm3
3.1-3.4 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Saudi Arabia, South Korea
China, India, Indonesia, Kazakhstan, Russia, South Korea, Thailand, Turkey
Africa
Eritrea, Ethiopia, Ghana, South Africa, Western Africa
Morocco, South Africa
Europe
England, Finland, France, Germany, Great Britain, Greece, United Kingdom
Finland, France, Georgia, Germany, Great Britain, Italy, Kazakhstan, Netherlands, Norway, Spain, Switzerland
Deposits in Western Continents
North America
USA
Canada, USA
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New Zealand, Western Australia