Definition
Andesite is a dark, fine-grained, brown or greyish intermediate volcanic rock which is a commonly found in lava
Banded iron formation are distinctive units of sedimentary rock that are almost always of Precambrian age
History
Origin
North America
Western Australia, Minnesota
Discoverer
Theodor von Gümbel
Johann Gottlob Lehmann
Etymology
From Andes mountains, where it is found in abundance
From its formation process
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
Volcanic
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Banded, Trellis
Color
Bluish - Grey, Grey, Pink, Yellow
Red, Reddish Brown
Maintenance
More
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull and Soft
Layered, Banded, Veined and Shiny
Architecture
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration, Kitchens
Decorative Aggregates, Homes
Exterior Uses
Office Buildings, Roof Tiles
Paving Stone, Office Buildings
Other Architectural Uses
Curbing
Curbing, Whetstones
Industry
Construction Industry
Cobblestones, Construction Aggregate, for Road Aggregate
As Dimension Stone, Used for flooring, stair treads, borders and window sills.
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Other Uses
Commercial Uses
Commemorative Tablets, Creating Artwork
As a touchstone, Cemetery Markers, Creating Artwork
Types
Icelandite
Algoma-type , Lake Superior-type, Superior-type and Taconite
Features
Generally rough to touch, High silica content, Is one of the oldest rock
Is one of the oldest rock
Archaeological Significance
Monuments
-
-
Famous Monuments
Middle of the Earth in Ecuador
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
Formation
Andesite is a fine-grained igneous rock that forms when the magma is erupted onto the surface and is crystallized quickly.
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.
Composition
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Ilmenite, Magnetite, Plagioclase, Pyroxene, Zircon
Hematite, Magnetite, Quartz
Compound Content
Silicon Dioxide
Fe, Iron(III) Oxide, Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Chemical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Coastal Erosion, Wind Erosion
Physical Properties
Hardness
75.5-6
1
7
👆🏻
Grain Size
Very fine-grained
Large and Coarse Grained
Fracture
Uneven
Uneven, Splintery or Conchoidal
Streak
White
White
Porosity
Less Porous
Highly Porous
Luster
Vitreous
Earthy
Compressive Strength
225.00 N/mm2220.00 N/mm2
0.15
450
👆🏻
Cleavage
-
-
Toughness
1.1
1.5
Specific Gravity
2.5-2.85.0-5.3
0
8.4
👆🏻
Transparency
Opaque
Translucent to Opaque
Density
2.11-2.36 g/cm3-9999 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
2.39 kJ/Kg K3.20 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
India, Indonesia, Japan, Nepal, South Korea
China, India, Iran, Iraq, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Egypt, Ethiopia, Morocco, Namibia, South Africa, Tanzania
Kenya, Morocco, South Africa, Tanzania
Europe
Austria, Finland, Germany, Italy, Romania, Turkey, United Kingdom
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Others
-
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Mexico, USA
Canada, Mexico, USA
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Bolivia, Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Western Australia
New South Wales, Queensland, South Australia, Western Australia