Definition
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Syenite is a coarse-grained igneous rock which is composed mainly of alkali feldspar and various ferromagnesian minerals
Discoverer
Unknown
Unknown
Etymology
From French anorthose plagioclase + -ite1
From French syénite, from Latin Syenites (lapis ) (stone) of Syene
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Foliated, Glassy
Earthy
Color
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Brown, Buff, Cream, Green, Grey, Pink, White
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Banded and Foilated
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Flooring, Homes, Hotels, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
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, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Curling
Cemetery Markers, Creating Artwork
Types
Proterozoic Anorthosite and Archean Anorthosite
Shonkinite
Features
Generally rough to touch, Is one of the oldest rock
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
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.
Syenites are formed due to alkaline igneous activities and are generally formed in thick continental crustal areas or in Cordilleran subduction zones.
Mineral Content
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Coarse Grained
Medium to Fine Coarse Grained
Porosity
Less Porous
Less Porous
Luster
Pearly to Subvitreous
Subvitreous to Dull
Specific Gravity
2.62-2.82
2.6-2.7
Transparency
Translucent
Opaque
Density
2.7-4 g/cm3
2.6-2.8 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
-
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
-
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Bulgaria, England, Germany, Norway, Romania, Switzerland
Deposits in Western Continents
South America
Bolivia, Colombia
Brazil, Chile
Deposits in Oceania Continent
Australia
Central Australia, South Australia, Western Australia
New Zealand, Queensland, South Australia, Western Australia
Anorthosite vs Syenite 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 Syenite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Anorthosite and Properties of Syenite. Learn more about Anorthosite vs Syenite in the next section. The interior uses of Anorthosite include Decorative aggregates, Floor tiles, Homes and Interior decoration whereas the interior uses of Syenite include Flooring, Homes, Hotels and Interior decoration. Due to some exceptional properties of Anorthosite and Syenite, 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 Syenite include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate, Landscaping, Making natural cement, Manufacture of magnesium and dolomite refractories.
More about Anorthosite and Syenite
Here you can know more about Anorthosite and Syenite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Anorthosite and Syenite consists of mineral content and compound content. The mineral content of Anorthosite includes Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene and mineral content of Syenite includes Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Anorthosite vs Syenite, 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, Syenite is available in brown, buff, cream, green, grey, pink, white colors. Appearance of Anorthosite is Layered, Banded, Veined and Shiny and that of Syenite is Banded and Foilated. Properties of rock is another aspect for Anorthosite vs Syenite. The hardness of Anorthosite is 5-6 and that of Syenite is 5.5-6. The types of Anorthosite are Proterozoic Anorthosite and Archean Anorthosite whereas types of Syenite are Shonkinite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Anorthosite and Syenite is white. The specific heat capacity of Anorthosite is 0.84 kJ/Kg K and that of Syenite 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 Syenite is heat resistant, impact resistant, wear resistant.