Definition
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Discoverer
Johann Gottlob Lehmann
Unknown
Etymology
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
from French néphéline, from Greek nephelē
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic, Splintery
Aphanitic
Color
Black, Brown, Buff, Green, Grey, Red, Yellow
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Appearance
Muddy
Skeletal
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts, Sculpture
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Pottery
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Types
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Peralkaline Nephelinite
Features
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Host Rock for Lead
Archaeological Significance
Famous Monuments
Jantar Mantar in India
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Formation
Shale forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are later compacted hence forming shale.
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
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Clinopyroxene, Nepheline, Plagioclase
Compound Content
Ca, Fe, Mg, Silicon Dioxide, Sodium
Ca, CaO, Carbon, Cl, MgO
Types of Metamorphism
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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
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Fine Grained
Porosity
Highly Porous
Less Porous
Luster
Dull
Vitreous to Metallic
Specific Gravity
2.2-2.8
2.4-2.9
Transparency
Opaque
Opaque
Density
2.4-2.8 g/cm3
2.5-3 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Bangladesh, China, India, Russia
Japan
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Rwanda, Tanzania
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
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Deposits in Western Continents
North America
USA
Canada, USA
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Colombia
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
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All about Shale and Nephelinite Properties
Know all about Shale and Nephelinite properties here. All properties of rocks are important as they define the type of rock and its application. Shale belongs to Sedimentary Rocks while Nephelinite belongs to Igneous Rocks.Texture of Shale is Clastic, Splintery whereas that of Nephelinite is Aphanitic. Shale appears Muddy and Nephelinite appears Skeletal. The luster of Shale is dull while that of Nephelinite is vitreous to metallic. Shale is available in black, brown, buff, green, grey, red, yellow colors whereas Nephelinite is available in black, brown, green, grey, white colors. The commercial uses of Shale are creating artwork, pottery and that of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo).