Definition
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism
Discoverer
Unknown
Abraham Gottlob Werner
Etymology
from French néphéline, from Greek nephelē
From Old French esclate, from esclat (French éclat)
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic
Foliated
Color
Black, Brown, Green, Grey, White
Black, Brown, Buff, Green, Light to Dark Grey, Purple, Red, Shades of Blue
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Bathrooms, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
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
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Blackboards, Commemorative Tablets, Laboratory bench tops, Standard material for the bed of Billiard table, Standard material for the beds of Pool and Snooker table, Tombstones, Used in aquariums, Writing Slates
Types
Peralkaline Nephelinite
Phyllite, Schist, and Slate
Features
Host Rock for Lead
Easily splits into thin plates, Surfaces are often shiny, Very fine grained rock
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.
Slate is a low grade metamorphic rock that is generally formed by metamorphosis of mudstone or shale, under relatively low pressure and temperature conditions.
Mineral Content
Clinopyroxene, Nepheline, Plagioclase
Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon
Compound Content
Ca, CaO, Carbon, Cl, MgO
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Contact Metamorphism
Burial Metamorphism, Cataclastic 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
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Very fine-grained
Streak
White
Light to dark brown
Porosity
Less Porous
Less Porous
Luster
Vitreous to Metallic
Dull
Specific Gravity
2.4-2.9
2.65-2.8
Transparency
Opaque
Opaque
Density
2.5-3 g/cm3
2.6-2.8 g/cm3
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Japan
China, India, Turkey
Africa
Rwanda, Tanzania
-
Europe
-
Belgium, France, Germany, Italy, Norway, Portugal, Spain, United Kingdom
Others
Hawaii Islands
Arctic
Deposits in Western Continents
North America
Canada, USA
USA
South America
Colombia
Brazil
Deposits in Oceania Continent
All about Nephelinite and Slate Properties
Know all about Nephelinite and Slate properties here. All properties of rocks are important as they define the type of rock and its application. Nephelinite belongs to Igneous Rocks while Slate belongs to Metamorphic Rocks.Texture of Nephelinite is Aphanitic whereas that of Slate is Foliated. Nephelinite appears Skeletal and Slate appears Dull. The luster of Nephelinite is vitreous to metallic while that of Slate is dull. Nephelinite is available in black, brown, green, grey, white colors whereas Slate is available in black, brown, buff, green, light to dark grey, purple, red, shades of blue colors. The commercial uses of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo) and that of Slate are blackboards, commemorative tablets, laboratory bench tops, standard material for the bed of billiard table, standard material for the beds of pool and snooker table, tombstones, used in aquariums, writing slates.