Definition
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Origin
Western Australia, Minnesota
-
Discoverer
Johann Gottlob Lehmann
Unknown
Etymology
From its formation process
From French anorthose plagioclase + -ite1
Class
Sedimentary Rocks
Igneous 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
Banded, Trellis
Foliated, Glassy
Color
Red, Reddish Brown
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Homes
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Exterior Uses
Paving Stone, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration
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, for Road Aggregate
Antiquity Uses
Artifacts
Artifacts, Sculpture, Small Figurines
Commercial Uses
As a touchstone, Cemetery Markers, Creating Artwork
Creating Artwork, Curling
Types
Algoma-type , Lake Superior-type, Superior-type and Taconite
Proterozoic Anorthosite and Archean Anorthosite
Features
Is one of the oldest rock
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.
Anorthosite is a phaneritic, intrusive igneous rock which is characterized by a predominance of plagioclase feldspar which is almost 90–100%, and a minimal mafic component.
Mineral Content
Hematite, Magnetite, Quartz
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Compound Content
Fe, Iron(III) Oxide, Silicon Dioxide
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Types of Metamorphism
-
Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Chemical Weathering
Biological Weathering
Types of Erosion
Coastal Erosion, Wind Erosion
Chemical Erosion, Wind Erosion
Grain Size
Large and Coarse Grained
Coarse Grained
Fracture
Uneven, Splintery or Conchoidal
Irregular
Porosity
Highly Porous
Less Porous
Luster
Earthy
Pearly to Subvitreous
Specific Gravity
5.0-5.3
2.62-2.82
Transparency
Translucent to Opaque
Translucent
Density
-9999 g/cm3
2.7-4 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Iraq, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
-
Africa
Kenya, Morocco, South Africa, Tanzania
-
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Others
Greenland, Mid-Atlantic Ridge
-
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada
South America
Bolivia, Brazil
Bolivia, Colombia
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
Central Australia, South Australia, Western Australia
Banded iron formation vs Anorthosite 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 Anorthosite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Banded iron formation and Properties of Anorthosite. Learn more about Banded iron formation vs Anorthosite in the next section. The interior uses of Banded iron formation include Decorative aggregates and Homes whereas the interior uses of Anorthosite include Decorative aggregates, Floor tiles, Homes and Interior decoration. Due to some exceptional properties of Banded iron formation and Anorthosite, 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 Anorthosite include As dimension stone, Cement manufacture, For road aggregate.
More about Banded iron formation and Anorthosite
Here you can know more about Banded iron formation and Anorthosite. 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 Anorthosite consists of mineral content and compound content. The mineral content of Banded iron formation includes Hematite, Magnetite, Quartz and mineral content of Anorthosite includes Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene. You can also check out the list of all Sedimentary Rocks. When we have to compare Banded iron formation vs Anorthosite, 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, Anorthosite is available in black, bluish - grey, brown, green, grey, light greenish grey, pink, white colors. Appearance of Banded iron formation is Layered, Banded, Veined and Shiny and that of Anorthosite is Layered, Banded, Veined and Shiny. Properties of rock is another aspect for Banded iron formation vs Anorthosite. The hardness of Banded iron formation is 5.5-6 and that of Anorthosite is 5-6. The types of Banded iron formation are Algoma-type , Lake Superior-type, Superior-type and Taconite whereas types of Anorthosite are Proterozoic Anorthosite and Archean Anorthosite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Banded iron formation and Anorthosite is white. The specific heat capacity of Banded iron formation is 3.20 kJ/Kg K and that of Anorthosite is 0.84 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 Anorthosite is heat resistant, impact resistant, pressure resistant, scratch resistant, wear resistant.