Definition
Syenite is a coarse-grained igneous rock which is composed mainly of alkali feldspar and various ferromagnesian minerals
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 syénite, from Latin Syenites (lapis ) (stone) of Syene
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, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Color
Brown, Buff, Cream, Green, Grey, Pink, White
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded and Foilated
Skeletal
Interior Uses
Flooring, Homes, Hotels, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Cemetery Markers, Creating Artwork
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Types
Shonkinite
Peralkaline Nephelinite
Features
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
Host Rock for Lead
Archaeological Significance
Formation
Syenites are formed due to alkaline igneous activities and are generally formed in thick continental crustal areas or in Cordilleran subduction zones.
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, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Clinopyroxene, Nepheline, Plagioclase
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Ca, CaO, Carbon, Cl, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Porosity
Less Porous
Less Porous
Luster
Subvitreous to Dull
Vitreous to Metallic
Specific Gravity
2.6-2.7
2.4-2.9
Transparency
Opaque
Opaque
Density
2.6-2.8 g/cm3
2.5-3 g/cm3
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Japan
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Rwanda, Tanzania
Europe
Bulgaria, England, Germany, Norway, Romania, Switzerland
-
Deposits in Western Continents
North America
USA
Canada, USA
South America
Brazil, Chile
Colombia
Deposits in Oceania Continent
Australia
New Zealand, Queensland, South Australia, Western Australia
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Syenite vs Nephelinite 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. Syenite vs Nephelinite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Syenite and Properties of Nephelinite. Learn more about Syenite vs Nephelinite in the next section. The interior uses of Syenite include Flooring, Homes, Hotels and Interior decoration whereas the interior uses of Nephelinite include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Syenite and Nephelinite, they have various applications in construction industry. The uses of Syenite in construction industry include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate, Landscaping, Making natural cement, Manufacture of magnesium and dolomite refractories and that of Nephelinite include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate.
More about Syenite and Nephelinite
Here you can know more about Syenite and Nephelinite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Syenite and Nephelinite consists of mineral content and compound content. The mineral content of Syenite includes Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz and mineral content of Nephelinite includes Clinopyroxene, Nepheline, Plagioclase. You can also check out the list of all Igneous Rocks. When we have to compare Syenite vs Nephelinite, the texture, color and appearance plays an important role in determining the type of rock. Syenite is available in brown, buff, cream, green, grey, pink, white colors whereas, Nephelinite is available in black, brown, green, grey, white colors. Appearance of Syenite is Banded and Foilated and that of Nephelinite is Skeletal. Properties of rock is another aspect for Syenite vs Nephelinite. The hardness of Syenite is 5.5-6 and that of Nephelinite is 6.5. The types of Syenite are Shonkinite whereas types of Nephelinite are Peralkaline Nephelinite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Syenite and Nephelinite is white. The specific heat capacity of Syenite is 0.92 kJ/Kg K and that of Nephelinite is 0.88 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Syenite is heat resistant, impact resistant, wear resistant whereas Nephelinite is heat resistant.