Definition
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
Phyllite is a fine-grained metamorphic rock with a well-developed laminar structure, and is intermediate between slate and schist rocks
History
Origin
Western Australia, Minnesota
-
Discoverer
Johann Gottlob Lehmann
Unknown
Etymology
From its formation process
From Greek phullon leaf + -ite1
Class
Sedimentary Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Family
Group
-
-
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Banded, Trellis
Phyllitic Sheen, Slaty
Color
Red, Reddish Brown
Black to Grey, Light Greenish Grey
Maintenance
Less
More
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Layered, Banded, Veined and Shiny
Crinkled or Wavy
Architecture
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
Industry
Construction Industry
As Dimension Stone, Used for flooring, stair treads, borders and window sills.
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar, Roadstone
Medical Industry
-
-
Antiquity Uses
Artifacts
Artifacts, Sculpture
Other Uses
Commercial Uses
As a touchstone, Cemetery Markers, Creating Artwork
Cemetery Markers, Commemorative Tablets, Creating Artwork, Writing Slates
Types
Algoma-type , Lake Superior-type, Superior-type and Taconite
Phyllite
Features
Is one of the oldest rock
Easily splits into thin plates, Is one of the oldest rock, Surfaces are often shiny
Archaeological Significance
Monuments
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-
Famous Monuments
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-
Sculpture
-
-
Famous Sculptures
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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.
Phyllite is a metamorphic rock which is formed by regional metamorphism of argillaceous sediments since their cleavage arose due to deviatoric stress.
Composition
Mineral Content
Hematite, Magnetite, Quartz
Albite, Alusite, Amphibole, Apatite, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc, Zircon
Compound Content
Fe, Iron(III) Oxide, Silicon Dioxide
CaO, Carbon Dioxide, MgO
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
-
Weathering
✔
✘
✔
✘
Types of Weathering
Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Coastal Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
5.5-61-2
1
7
👆🏻
Grain Size
Large and Coarse Grained
Medium to Fine Coarse Grained
Fracture
Uneven, Splintery or Conchoidal
Conchoidal
Streak
White
White
Porosity
Highly Porous
Highly Porous
Luster
Earthy
Phyllitic
Compressive Strength
220.00 N/mm250.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Crenulation and Pervasive
Toughness
1.5
1.2
Specific Gravity
5.0-5.32.72-2.73
0
8.4
👆🏻
Transparency
Translucent to Opaque
Opaque
Density
-9999 g/cm32.18-3.3 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
3.20 kJ/Kg K0.79 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Pressure Resistant, Water Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Iraq, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
Africa
Kenya, Morocco, South Africa, Tanzania
Egypt, Ethiopia, Morocco, Nigeria, South Africa
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Others
Greenland, Mid-Atlantic Ridge
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Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
Bolivia, Brazil
Brazil, Colombia, Guyana
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
New South Wales, New Zealand, Queensland