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