Definition
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Gritstone or grit is a hard, coarse-grained, siliceous sandstone
Origin
-
Pennines, England
Discoverer
Unknown
J.J. Ferber
Etymology
From French anorthose plagioclase + -ite1
From Grit + Stone
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Foliated, Glassy
Earthy
Color
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Beige, Black, Brown, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Layered and Foliated
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Countertops, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
Construction Aggregate, Roadstone
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Curling
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO), Tombstones
Types
Proterozoic Anorthosite and Archean Anorthosite
Sedimentary rock
Features
Generally rough to touch, Is one of the oldest rock
Available in Lots of Colors and Patterns, Generally rough to touch, Very fine grained 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.
Gritstone is a type of sedimentary rock which was formed on the floors of wide river deltas where the grit deposits were laid down, with every tide or flood dumping another layer of sediment.
Mineral Content
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Calcite, Clay Minerals, Feldspar, Micas, Quartz
Compound Content
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism
-
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion
Grain Size
Coarse Grained
Coarse Grained
Fracture
Irregular
Conchoidal
Porosity
Less Porous
Highly Porous
Luster
Pearly to Subvitreous
Dull
Specific Gravity
2.62-2.82
2.250
Transparency
Translucent
Opaque
Density
2.7-4 g/cm3
2.2 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
-
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
-
Namibia, Nigeria, South Africa
Europe
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Austria, Denmark, Germany, Great Britain, Netherlands, Poland, Sweden, Switzerland, United Kingdom
Deposits in Western Continents
North America
Canada
Canada, USA
South America
Bolivia, Colombia
Brazil
Deposits in Oceania Continent
Australia
Central Australia, South Australia, Western Australia
New South Wales, New Zealand, Western Australia
Anorthosite vs Gritstone 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 Gritstone characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Anorthosite and Properties of Gritstone. Learn more about Anorthosite vs Gritstone in the next section. The interior uses of Anorthosite include Decorative aggregates, Floor tiles, Homes and Interior decoration whereas the interior uses of Gritstone include Countertops, Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Anorthosite and Gritstone, 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 Gritstone include Construction aggregate, Roadstone.
More about Anorthosite and Gritstone
Here you can know more about Anorthosite and Gritstone. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Anorthosite and Gritstone consists of mineral content and compound content. The mineral content of Anorthosite includes Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene and mineral content of Gritstone includes Calcite, Clay Minerals, Feldspar, Micas, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Anorthosite vs Gritstone, 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, Gritstone is available in beige, black, brown, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors. Appearance of Anorthosite is Layered, Banded, Veined and Shiny and that of Gritstone is Layered and Foliated. Properties of rock is another aspect for Anorthosite vs Gritstone. The hardness of Anorthosite is 5-6 and that of Gritstone is 6-7. The types of Anorthosite are Proterozoic Anorthosite and Archean Anorthosite whereas types of Gritstone are Sedimentary rock. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Anorthosite and Gritstone is white. The specific heat capacity of Anorthosite is 0.84 kJ/Kg K and that of Gritstone 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 Gritstone is heat resistant, impact resistant, pressure resistant.