Definition
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
Eclogite is an extreme metamorphic rock, formed by regional metamorphism of basalt rock under very high pressure and temperature
Origin
Western Australia, Minnesota
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Discoverer
Johann Gottlob Lehmann
René Just Haüy
Etymology
From its formation process
From French, Greek eklogē selection with reference to the selective content of the rock + -ite1
Class
Sedimentary 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
Banded, Trellis
Earthy
Color
Red, Reddish Brown
Black, Brown, Green, Grey, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Dull, Banded and Foilated
Interior Uses
Decorative Aggregates, Homes
Decorative Aggregates, Interior Decoration
Exterior Uses
Paving Stone, Office Buildings
Paving Stone, Garden Decoration
Other Architectural Uses
Curbing, Whetstones
Curbing
Construction Industry
As Dimension Stone, Used for flooring, stair treads, borders and window sills.
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Medical Industry
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In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
Antiquity Uses
Artifacts
Artifacts
Commercial Uses
As a touchstone, Cemetery Markers, Creating Artwork
Creating Artwork, Gemstone
Types
Algoma-type , Lake Superior-type, Superior-type and Taconite
Eclogite
Features
Is one of the oldest rock
Available in Lots of Colors and Patterns, Generally rough to touch, Is one of the oldest rock
Archaeological Significance
Formation
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.
Eclogite forms from high-pressure metamorphism of mafic igneous rocks mainly, basalt or gabbro as it plunges into the mantle in a subduction zone.
Mineral Content
Hematite, Magnetite, Quartz
Amphibole, Coesite, Corundum, Dolomite, Garnet, Kyanite, Lawsonite, Paragonite, Phengite, Pyroxene, Quartz, Rutile, Zoisite
Compound Content
Fe, Iron(III) Oxide, Silicon Dioxide
Aluminium Oxide, NaCl, CaO, Carbon Dioxide, Iron(III) Oxide, Magnesium Carbonate, MgO, Sodium Oxide, Potassium, Sodium
Types of Metamorphism
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Types of Weathering
Chemical Weathering
Mechanical Weathering
Types of Erosion
Coastal Erosion, Wind Erosion
Chemical Erosion, Sea Erosion
Grain Size
Large and Coarse Grained
Fine Grained
Fracture
Uneven, Splintery or Conchoidal
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Porosity
Highly Porous
Less Porous
Luster
Earthy
Subvitreous to Dull
Specific Gravity
5.0-5.3
2.86-2.87
Transparency
Translucent to Opaque
Opaque
Density
-9999 g/cm3
3.2-3.6 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Iraq, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
India, Kazakhstan, Kuwait, Russia, South Korea, Thailand, Turkey
Africa
Kenya, Morocco, South Africa, Tanzania
Ethiopia, Morocco, South Africa
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
France, Germany, Italy, Norway, Scotland
Others
Greenland, Mid-Atlantic Ridge
Greenland
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, Costa Rica, Panama, USA
South America
Bolivia, Brazil
Argentina, Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
Central Australia, New Zealand, Queensland