Definition
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Origin
Western Australia, Minnesota
Brazil
Discoverer
Johann Gottlob Lehmann
Unknown
Etymology
From its formation process
from French néphéline, from Greek nephelē
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Banded, Trellis
Aphanitic
Color
Red, Reddish Brown
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Skeletal
Interior Uses
Decorative Aggregates, Homes
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
Paving Stone, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing, Whetstones
Curbing
Construction Industry
As Dimension Stone, Used for flooring, stair treads, borders and window sills.
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
As a touchstone, Cemetery Markers, Creating Artwork
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Types
Algoma-type , Lake Superior-type, Superior-type and Taconite
Peralkaline Nephelinite
Features
Is one of the oldest rock
Host Rock for Lead
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.
Nephelinite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Hematite, Magnetite, Quartz
Clinopyroxene, Nepheline, Plagioclase
Compound Content
Fe, Iron(III) Oxide, Silicon Dioxide
Ca, CaO, Carbon, Cl, MgO
Types of Metamorphism
-
Contact Metamorphism
Types of Weathering
Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Wind Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Large and Coarse Grained
Fine Grained
Fracture
Uneven, Splintery or Conchoidal
Flat
Porosity
Highly Porous
Less Porous
Luster
Earthy
Vitreous to Metallic
Specific Gravity
5.0-5.3
2.4-2.9
Transparency
Translucent to Opaque
Opaque
Density
-9999 g/cm3
2.5-3 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
Japan
Africa
Kenya, Morocco, South Africa, Tanzania
Rwanda, Tanzania
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
-
Others
Greenland, Mid-Atlantic Ridge
Hawaii Islands
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Bolivia, Brazil
Colombia
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
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Banded iron formation vs Nephelinite 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. Banded iron formation vs Nephelinite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Banded iron formation and Properties of Nephelinite. Learn more about Banded iron formation vs Nephelinite in the next section. The interior uses of Banded iron formation include Decorative aggregates and Homes whereas the interior uses of Nephelinite include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Banded iron formation and Nephelinite, they have various applications in construction industry. The uses of Banded iron formation in construction industry include As dimension stone, Used for flooring, stair treads, borders and window sills. and that of Nephelinite include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate.
More about Banded iron formation and Nephelinite
Here you can know more about Banded iron formation and Nephelinite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Banded iron formation and Nephelinite consists of mineral content and compound content. The mineral content of Banded iron formation includes Hematite, Magnetite, Quartz and mineral content of Nephelinite includes Clinopyroxene, Nepheline, Plagioclase. You can also check out the list of all Sedimentary Rocks. When we have to compare Banded iron formation vs Nephelinite, the texture, color and appearance plays an important role in determining the type of rock. Banded iron formation is available in red, reddish brown colors whereas, Nephelinite is available in black, brown, green, grey, white colors. Appearance of Banded iron formation is Layered, Banded, Veined and Shiny and that of Nephelinite is Skeletal. Properties of rock is another aspect for Banded iron formation vs Nephelinite. The hardness of Banded iron formation is 5.5-6 and that of Nephelinite is 6.5. The types of Banded iron formation are Algoma-type , Lake Superior-type, Superior-type and Taconite whereas types of Nephelinite are Peralkaline Nephelinite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Banded iron formation and Nephelinite is white. The specific heat capacity of Banded iron formation is 3.20 kJ/Kg K and that of Nephelinite is 0.88 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Banded iron formation is heat resistant, impact resistant, pressure resistant, wear resistant whereas Nephelinite is heat resistant.