Definition
Kimberlite is a rare, blue-tinged, coarse-grained intrusive igneous rock, which sometimes contains diamonds and is mostly found in South Africa and Siberia.
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Origin
Kimberley, South Africa
Brazil
Discoverer
John W. Judd
Unknown
Etymology
From Kimberley + -ite, from the name of the South African town of Kimberley where the rock was first found.
from French néphéline, from Greek nephelē
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Porphyritic
Aphanitic
Color
Black, Bluish - Grey, Brown, Dark Greenish - Grey, Green, Grey
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Banded
Skeletal
Interior Uses
Countertops, Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Taken as a Supplement for Calcium or Magnesium
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Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO)
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Types
Basaltic Kimberlites and Micaceous Kimberlites
Peralkaline Nephelinite
Features
Always found as volcanic pipes over deep continental crust, Host rock for Diamond, Is one of the oldest rock, Surfaces are often shiny
Host Rock for Lead
Archaeological Significance
Formation
Kimberlite is an igneous rock and is the main source of diamonds. Its formation takes place deep beneath the Earth’s surface between 150 to 450 kilometres, and are erupted rapidly and violently.
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
Garnet, Olivine, Phlogopite, Pyroxene
Clinopyroxene, Nepheline, Plagioclase
Compound Content
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, 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
Fine to Coarse Grained
Fine Grained
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Vitreous to Metallic
Specific Gravity
2.86-2.87
2.4-2.9
Transparency
Translucent to Opaque
Opaque
Density
2.95-2.96 g/cm3
2.5-3 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Africa
Angola, Botswana, Cameroon, Ethiopia, South Africa
Rwanda, Tanzania
Europe
England, Hungary, Iceland, United Kingdom
-
Others
Antarctica
Hawaii Islands
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Argentina, Colombia, Ecuador
Colombia
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, South Australia, Western Australia
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All about Kimberlite and Nephelinite Properties
Know all about Kimberlite and Nephelinite properties here. All properties of rocks are important as they define the type of rock and its application. Kimberlite and Nephelinite belong to Igneous Rocks.Texture of Kimberlite is Porphyritic whereas that of Nephelinite is Aphanitic. Kimberlite appears Dull and Banded and Nephelinite appears Skeletal. The luster of Kimberlite is subvitreous to dull while that of Nephelinite is vitreous to metallic. Kimberlite is available in black, bluish - grey, brown, dark greenish - grey, green, grey colors whereas Nephelinite is available in black, brown, green, grey, white colors. The commercial uses of Kimberlite are an oil and gas reservoir, as a feed additive for livestock, gemstone, metallurgical flux, production of lime, soil conditioner, source of magnesia (mgo) and that of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo).