Definition
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Argillites are highly compact sedimentary or slightly metamorphosed rocks that consist largely or wholly of particles of clay or silt but lack the fissility of shale or the cleavage characteristic of slate
Discoverer
Unknown
Unknown
Etymology
From French anorthose plagioclase + -ite1
From Latin Argilla (clay) and -ite in English which became agrilla+ -ite = Argillite
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated, Glassy
Clastic, Polished
Color
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Dark Grey to Black, Pink, Red, White
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Rough and Dull
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing, Whetstones
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
Used for flooring, stair treads, borders and window sills.
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Curling
Fire resistant, Used to manufracture paperweights and bookends
Types
Proterozoic Anorthosite and Archean Anorthosite
Metamorphic rock
Features
Generally rough to touch, Is one of the oldest rock
Is one of the oldest rock
Archaeological Significance
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.
An argillite is a fine-grained sedimentary rock mainly composed of clay particles which forms from lithified muds which contain variable amounts of silt-sized particles.
Mineral Content
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
Compound Content
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Iron(III) Oxide, Potassium Oxide, MgO, Silicon Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism
-
Types of Weathering
Biological Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Wind Erosion
Chemical Erosion
Grain Size
Coarse Grained
Fine Grained
Fracture
Irregular
Conchoidal to Uneven
Streak
White
White to Grey
Porosity
Less Porous
Highly Porous
Luster
Pearly to Subvitreous
Waxy and Dull
Specific Gravity
2.62-2.82
2.56-2.68
Transparency
Translucent
Opaque
Density
2.7-4 g/cm3
2.54-2.66 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
-
Bangladesh, China, India, Russia
Africa
-
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Deposits in Western Continents
South America
Bolivia, Colombia
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
Central Australia, South Australia, Western Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
Anorthosite vs Argillite 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 Argillite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Anorthosite and Properties of Argillite. Learn more about Anorthosite vs Argillite in the next section. The interior uses of Anorthosite include Decorative aggregates, Floor tiles, Homes and Interior decoration whereas the interior uses of Argillite include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Anorthosite and Argillite, 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 Argillite include Used for flooring, stair treads, borders and window sills..
More about Anorthosite and Argillite
Here you can know more about Anorthosite and Argillite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Anorthosite and Argillite consists of mineral content and compound content. The mineral content of Anorthosite includes Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene and mineral content of Argillite includes Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Anorthosite vs Argillite, 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, Argillite is available in dark grey to black, pink, red, white colors. Appearance of Anorthosite is Layered, Banded, Veined and Shiny and that of Argillite is Rough and Dull. Properties of rock is another aspect for Anorthosite vs Argillite. The hardness of Anorthosite is 5-6 and that of Argillite is 2-3. The types of Anorthosite are Proterozoic Anorthosite and Archean Anorthosite whereas types of Argillite are Metamorphic rock. 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 Argillite is white to grey. The specific heat capacity of Anorthosite is 0.84 kJ/Kg K and that of Argillite is 0.87 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 Argillite is heat resistant, impact resistant.