Definition
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
Mylonite is a metamorphic rock formed by ductile deformation during intense shearing encountered during folding and faulting, a process termed cataclastic or dynamic metamorphism
Origin
New Zealand
New Zealand
Discoverer
Ferdinand von Hochstetter
Unknown
Etymology
From the name of Dun Mountain, New Zealand, + -ite1
From Greek mulōn mill + -ite
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Phaneritic
Foliated
Color
Dark Greenish - Grey
Black to Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Rough and Shiny
Dull, Banded and Foilated
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
for Road Aggregate, Landscaping, Roadstone
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Creating Artwork, Gemstone, Jewelry, Source of Chromite, Platinum, Nickel and Garnet, Source of Diamonds
Creating Artwork, Gemstone, Jewelry
Types
Dunite
Blastomylonites, Ultramylonites and Phyllonites
Features
Constitutes upper part of the Earth's mantle, Generally rough to touch, Host rock for Diamond, Is one of the oldest rock
Surfaces are often shiny
Archaeological Significance
Formation
Dunite is a plutonic ultramafic igneous rock consisting almost m olivine. It can be formed in two ways.
Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.
Mineral Content
Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene
Porphyroblasts
Compound Content
Ca, CaO, Fe, Potassium, Silicon Dioxide, Sodium, Titanium Dioxide
Aluminium Oxide, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Grain Size
Coarse Grained
Fine Grained
Fracture
Irregular
Conchoidal
Porosity
Less Porous
Highly Porous
Specific Gravity
3-3.01
2.97-3.05
Transparency
Translucent to Opaque
Opaque
Density
2.84-2.85 g/cm3
2.6-4.8 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Kazakhstan, Russia, South Korea, Thailand, Turkey
China, India, Indonesia, Saudi Arabia, South Korea
Africa
Morocco, South Africa
Eritrea, Ethiopia, Ghana, South Africa, Western Africa
Europe
Finland, France, Georgia, Germany, Great Britain, Italy, Kazakhstan, Netherlands, Norway, Spain, Switzerland
England, Finland, France, Germany, Great Britain, Greece, United Kingdom
Deposits in Western Continents
North America
Canada, USA
USA
South America
Argentina, Brazil, Colombia, Ecuador, Venezuela
-
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
Central Australia, Western Australia