Definition
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
Icelandite belongs to volcanic igneous rocks which is rich in iron and belongs to andesite rock
History
Origin
Western Australia, Minnesota
Iceland
Discoverer
Johann Gottlob Lehmann
Ian S. E. Carmichael
Etymology
From its formation process
From its origin place near Cenozoic volcano near the parsonage Þingmúli in East Iceland
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Family
Group
-
Volcanic
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Banded, Trellis
Aphanitic to Porphyritic
Color
Red, Reddish Brown
Bluish - Grey, Grey, Pink, Yellow
Maintenance
Less
More
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Layered, Banded, Veined and Shiny
Dull and Soft
Architecture
Interior Uses
Decorative Aggregates, Homes
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration, Kitchens
Exterior Uses
Paving Stone, Office Buildings
Office Buildings, Roof Tiles
Other Architectural Uses
Curbing, Whetstones
Curbing
Industry
Construction Industry
As Dimension Stone, Used for flooring, stair treads, borders and window sills.
Cobblestones, Construction Aggregate, for Road Aggregate
Medical Industry
-
-
Antiquity Uses
Artifacts
Artifacts, Jewellery, Sculpture, Small Figurines
Other Uses
Commercial Uses
As a touchstone, Cemetery Markers, Creating Artwork
Cemetery Markers, Creating Artwork
Types
Algoma-type , Lake Superior-type, Superior-type and Taconite
Intermediate volcanic rock
Features
Is one of the oldest rock
Generally rough to touch, High silica content, Is one of the oldest rock
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Present
Absent
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.
Icelandite 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.
Composition
Mineral Content
Hematite, Magnetite, Quartz
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Ilmenite, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Compound Content
Fe, Iron(III) Oxide, Silicon Dioxide
Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Chemical Weathering
Biological Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Coastal Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Sea Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
5.5-67
1
7
👆🏻
Grain Size
Large and Coarse Grained
Very fine-grained
Fracture
Uneven, Splintery or Conchoidal
Uneven
Streak
White
White
Porosity
Highly Porous
Less Porous
Luster
Earthy
Vitreous
Compressive Strength
220.00 N/mm2200.00 N/mm2
0.15
450
👆🏻
Cleavage
-
-
Toughness
1.5
1.1
Specific Gravity
5.0-5.32.5-2.8
0
8.4
👆🏻
Transparency
Translucent to Opaque
Opaque
Density
-9999 g/cm32.11-2.36 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
3.20 kJ/Kg K2.39 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Iraq, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
India, Indonesia, Japan, Nepal, South Korea
Africa
Kenya, Morocco, South Africa, Tanzania
Egypt, Ethiopia, Morocco, Namibia, South Africa, Tanzania
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Austria, Finland, Germany, Italy, Romania, Turkey, United Kingdom
Others
Greenland, Mid-Atlantic Ridge
-
Deposits in Western Continents
North America
Canada, Mexico, USA
Mexico, USA
South America
Bolivia, Brazil
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
New South Wales, New Zealand, Western Australia