Definition
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
Rhomb-porphyry is a porphyritic igneous rock with abundant wedge or lens shaped anorthoclase or feldspar phenocrysts
Origin
Western Australia, Minnesota
Unknown
Discoverer
Unknown
Unknown
Etymology
From its formation process
From Latin term that means purple
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Volcanic
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Banded, Trellis
Aphanitic to Porphyritic
Color
Red, Reddish Brown
Black, Brown, Colourless, Green, Grey, Pink, White
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Rough
Interior Uses
Decorative Aggregates, Homes
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
Paving Stone, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing, Whetstones
Curbing
Construction Industry
As Dimension Stone, Used for flooring, stair treads, borders and window sills.
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
As a touchstone, Cemetery Markers, Creating Artwork
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Metallurgical Flux, Soil Conditioner, Source of Magnesia (MgO)
Types
Algoma-type , Lake Superior-type, Superior-type and Taconite
Not Available
Features
Is one of the oldest rock
Host Rock for Lead
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Figurines
Not Yet Used
Used
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.
Rhomb-porphyry 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
Alkali feldspar, Biotite, Plagioclase, Pyroxene
Compound Content
Fe, Iron(III) Oxide, Silicon Dioxide
CaO, Cl, MgO
Types of Metamorphism
Not Applicable
Impact Metamorphism
Types of Weathering
Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion
Grain Size
Large and Coarse Grained
Fine Grained
Fracture
Uneven, Splintery or Conchoidal
Conchoidal
Porosity
Highly Porous
Very Less Porous
Luster
Earthy
Subvitreous to Dull
Compressive Strength
Not Available
Cleavage
Imperfect
Perfect
Specific Gravity
5.0-5.3
2.86
Transparency
Translucent to Opaque
Translucent
Density
Not Available
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Iraq, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Not Yet Found
Africa
Kenya, Morocco, South Africa, Tanzania
Not Yet Found
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Bulgaria
Others
Greenland, Mid-Atlantic Ridge
Not Yet Found
Deposits in Western Continents
North America
Canada, Mexico, USA
USA
South America
Bolivia, Brazil
Not Yet Found
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
Not Yet Found
All about Banded iron formation and Rhomb Porphyry Properties
Know all about Banded iron formation and Rhomb Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Banded iron formation belongs to Sedimentary Rocks while Rhomb Porphyry belongs to Igneous Rocks.Texture of Banded iron formation is Banded, Trellis whereas that of Rhomb Porphyry is Aphanitic to Porphyritic. Banded iron formation appears Layered, Banded, Veined and Shiny and Rhomb Porphyry appears Rough. The luster of Banded iron formation is earthy while that of Rhomb Porphyry is subvitreous to dull. Banded iron formation is available in red, reddish brown colors whereas Rhomb Porphyry is available in black, brown, colourless, green, grey, pink, white colors. The commercial uses of Banded iron formation are as a touchstone, cemetery markers, creating artwork and that of Rhomb Porphyry are an oil and gas reservoir, as a feed additive for livestock, metallurgical flux, soil conditioner, source of magnesia (mgo).