Definition
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
Origin
Unknown
USA, Australia
Discoverer
Unknown
Tornebohm
Etymology
From French anorthose plagioclase + -ite1
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Group
Plutonic
Not Applicable
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated, Glassy
Earthy, Mud-rich, Rough
Color
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Black, Brown, Colourless, Green, Grey, White
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Dull
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
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, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
Not Yet Used
Not Applicable
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Curling
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Types
Proterozoic Anorthosite and Archean Anorthosite
Endoskarns
Features
Generally rough to touch, Is one of the oldest rock
Host Rock for Lead, Zinc and Copper Deposits
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Formation
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.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Compound Content
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering
Not Applicable
Types of Erosion
Chemical Erosion, Wind Erosion
Not Applicable
Grain Size
Coarse Grained
Fine Grained
Fracture
Irregular
Irregular
Streak
White
Light to dark brown
Porosity
Less Porous
Less Porous
Luster
Pearly to Subvitreous
Waxy and Dull
Toughness
Not Available
2.4
Specific Gravity
2.62-2.82
2.86
Transparency
Translucent
Opaque
Density
2.7-4 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Africa
Not Yet Found
South Africa, Western Africa
Europe
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada
Canada
South America
Bolivia, Colombia
Brazil, Colombia, Paraguay
Deposits in Oceania Continent
Australia
Central Australia, South Australia, Western Australia
Central Australia, Western Australia
Anorthosite vs Skarn 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. Anorthosite vs Skarn characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Anorthosite and Properties of Skarn. Learn more about Anorthosite vs Skarn in the next section. The interior uses of Anorthosite include Decorative aggregates, Floor tiles, Homes and Interior decoration whereas the interior uses of Skarn include Decorative aggregates, Entryways and Interior decoration. Due to some exceptional properties of Anorthosite and Skarn, they have various applications in construction industry. The uses of Anorthosite in construction industry include As dimension stone, Cement manufacture, For road aggregate and that of Skarn include 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, Gold and silver production, Manufacture of magnesium and dolomite refractories.
More about Anorthosite and Skarn
Here you can know more about Anorthosite and Skarn. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Anorthosite and Skarn consists of mineral content and compound content. The mineral content of Anorthosite includes Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene and mineral content of Skarn includes Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite. You can also check out the list of all Igneous Rocks. When we have to compare Anorthosite vs Skarn, the texture, color and appearance plays an important role in determining the type of rock. Anorthosite is available in black, bluish - grey, brown, green, grey, light greenish grey, pink, white colors whereas, Skarn is available in black, brown, colourless, green, grey, white colors. Appearance of Anorthosite is Layered, Banded, Veined and Shiny and that of Skarn is Dull. Properties of rock is another aspect for Anorthosite vs Skarn. The hardness of Anorthosite is 5-6 and that of Skarn is 6.5. The types of Anorthosite are Proterozoic Anorthosite and Archean Anorthosite whereas types of Skarn are Endoskarns. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Anorthosite is white while that of Skarn is light to dark brown. The specific heat capacity of Anorthosite is 0.84 kJ/Kg K and that of Skarn is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Anorthosite is heat resistant, impact resistant, pressure resistant, scratch resistant, wear resistant whereas Skarn is heat resistant.