Definition
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Discoverer
Unknown
Unknown
Etymology
From French anorthose plagioclase + -ite1
from French néphéline, from Greek nephelē
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated, Glassy
Aphanitic
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
Skeletal
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, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Curling
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Types
Proterozoic Anorthosite and Archean Anorthosite
Peralkaline Nephelinite
Features
Generally rough to touch, Is one of the oldest rock
Host Rock for Lead
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.
Nephelinite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Clinopyroxene, Nepheline, Plagioclase
Compound Content
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Ca, CaO, Carbon, Cl, MgO
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism
Contact Metamorphism
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Wind Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Coarse Grained
Fine Grained
Porosity
Less Porous
Less Porous
Luster
Pearly to Subvitreous
Vitreous to Metallic
Compressive Strength
Not Available
Cleavage
Irregular
Imperfect
Toughness
Not Available
2.7
Specific Gravity
2.62-2.82
2.4-2.9
Transparency
Translucent
Opaque
Density
2.7-4 g/cm3
2.5-3 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Africa
Not Yet Found
Rwanda, Tanzania
Europe
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Not Yet Found
Others
Not Yet Found
Hawaii Islands
Deposits in Western Continents
North America
Canada
Canada, USA
South America
Bolivia, Colombia
Colombia
Deposits in Oceania Continent
Australia
Central Australia, South Australia, Western Australia
Not Yet Found
All about Anorthosite and Nephelinite Properties
Know all about Anorthosite and Nephelinite properties here. All properties of rocks are important as they define the type of rock and its application. Anorthosite and Nephelinite belong to Igneous Rocks.Texture of Anorthosite is Foliated, Glassy whereas that of Nephelinite is Aphanitic. Anorthosite appears Layered, Banded, Veined and Shiny and Nephelinite appears Skeletal. The luster of Anorthosite is pearly to subvitreous while that of Nephelinite is vitreous to metallic. Anorthosite is available in black, bluish - grey, brown, green, grey, light greenish grey, pink, white colors whereas Nephelinite is available in black, brown, colourless, green, grey, white colors. The commercial uses of Anorthosite are creating artwork, curling and that of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo).