Definition
Dunite is a green to brownish coarse-grained igneous rock mainly consisting of olivine
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
Origin
New Zealand
Western Australia, Minnesota
Discoverer
Ferdinand von Hochstetter
Johann Gottlob Lehmann
Etymology
From the name of Dun Mountain, New Zealand, + -ite1
From its formation process
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Phaneritic
Banded, Trellis
Color
Dark Greenish - Grey
Red, Reddish Brown
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Rough and Shiny
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Homes
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Paving Stone, Office Buildings
Other Architectural Uses
Curbing
Curbing, Whetstones
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
As Dimension Stone, Used for flooring, stair treads, borders and window sills.
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Commercial Uses
Creating Artwork, Gemstone, Jewelry, Source of Chromite, Platinum, Nickel and Garnet, Source of Diamonds
As a touchstone, Cemetery Markers, Creating Artwork
Types
Dunite
Algoma-type , Lake Superior-type, Superior-type and Taconite
Features
Constitutes upper part of the Earth's mantle, Generally rough to touch, Host rock for Diamond, Is one of the oldest rock
Is one of the oldest rock
Archaeological Significance
Formation
Dunite is a plutonic ultramafic igneous rock consisting almost m olivine. It can be formed in two ways.
The banded iron layers are formed in sea water when oxygen is released by photosynthetic cyano-bacteria. The oxygen then combines with dissolved iron in ocean to form insoluble iron oxides, which precipitated out, forming a thin layer of banded iron formation on ocean floor.
Mineral Content
Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene
Hematite, Magnetite, Quartz
Compound Content
Ca, CaO, Fe, Potassium, Silicon Dioxide, Sodium, Titanium Dioxide
Fe, Iron(III) Oxide, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
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Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Chemical Weathering
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Coastal Erosion, Wind Erosion
Grain Size
Coarse Grained
Large and Coarse Grained
Fracture
Irregular
Uneven, Splintery or Conchoidal
Porosity
Less Porous
Highly Porous
Specific Gravity
3-3.01
5.0-5.3
Transparency
Translucent to Opaque
Translucent to Opaque
Density
2.84-2.85 g/cm3
-9999 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Kazakhstan, Russia, South Korea, Thailand, Turkey
China, India, Iran, Iraq, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Morocco, South Africa
Kenya, Morocco, South Africa, Tanzania
Europe
Finland, France, Georgia, Germany, Great Britain, Italy, Kazakhstan, Netherlands, Norway, Spain, Switzerland
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Others
-
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Canada, USA
Canada, Mexico, USA
South America
Argentina, Brazil, Colombia, Ecuador, Venezuela
Bolivia, Brazil
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New South Wales, Queensland, South Australia, Western Australia
Dunite vs Banded iron formation Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Dunite vs Banded iron formation characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Dunite and Properties of Banded iron formation. Learn more about Dunite vs Banded iron formation in the next section. The interior uses of Dunite include Decorative aggregates and Interior decoration whereas the interior uses of Banded iron formation include Decorative aggregates and Homes. Due to some exceptional properties of Dunite and Banded iron formation, they have various applications in construction industry. The uses of Dunite in construction industry include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar and that of Banded iron formation include As dimension stone, Used for flooring, stair treads, borders and window sills..
More about Dunite and Banded iron formation
Here you can know more about Dunite and Banded iron formation. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Dunite and Banded iron formation consists of mineral content and compound content. The mineral content of Dunite includes Amphibole, Chromite, Garnet, Magnesium, Olivine, Phlogopite, Plagioclase, Pyroxene and mineral content of Banded iron formation includes Hematite, Magnetite, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Dunite vs Banded iron formation, the texture, color and appearance plays an important role in determining the type of rock. Dunite is available in dark greenish - grey colors whereas, Banded iron formation is available in red, reddish brown colors. Appearance of Dunite is Rough and Shiny and that of Banded iron formation is Layered, Banded, Veined and Shiny. Properties of rock is another aspect for Dunite vs Banded iron formation. The hardness of Dunite is 3.5-4 and that of Banded iron formation is 5.5-6. The types of Dunite are Dunite whereas types of Banded iron formation are Algoma-type , Lake Superior-type, Superior-type and Taconite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Dunite and Banded iron formation is white. The specific heat capacity of Dunite is 1.25 kJ/Kg K and that of Banded iron formation is 3.20 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Dunite is heat resistant, pressure resistant, wear resistant whereas Banded iron formation is heat resistant, impact resistant, pressure resistant, wear resistant.