Definition
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Basaltic Trachyandesite is an extrusive igneous rock which is a type of Basalt rock and is formed by the rapid cooling of basaltic lava exposed at or very near the Earth's surface
Discoverer
Unknown
Unknown
Etymology
from French néphéline, from Greek nephelē
From its mineral and compound content and its relation with Basalt and Andesite rock
Class
Igneous Rocks
Igneous 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
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Color
Black, Brown, Green, Grey, White
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Skeletal
Dull and Soft
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Floor Tiles, Homes, Hotels, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing, Whetstones
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
An Oil and Gas Reservoir, Commemorative Tablets, Creating Artwork
Types
Peralkaline Nephelinite
Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite
Features
Host Rock for Lead
Has High structural resistance against erosion and climate, 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.
Basaltic Trachandesite is a fine-grained, hard rock that forms when bits of lava shoot out of volcanoes.
Mineral Content
Clinopyroxene, Nepheline, Plagioclase
Olivine, Plagioclase, Pyroxene
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
Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
-
Grain Size
Fine Grained
Fine Grained
Streak
White
White to Grey
Porosity
Less Porous
Less Porous
Luster
Vitreous to Metallic
-
Specific Gravity
2.4-2.9
2.8-3
Transparency
Opaque
Opaque
Density
2.5-3 g/cm3
2.9-3.1 g/cm3
Resistance
Heat Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Africa
Rwanda, Tanzania
South Africa
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Colombia
Brazil
Deposits in Oceania Continent
All about Nephelinite and Basaltic Trachyandesite Properties
Know all about Nephelinite and Basaltic Trachyandesite properties here. All properties of rocks are important as they define the type of rock and its application. Nephelinite and Basaltic Trachyandesite belong to Igneous Rocks.Texture of Nephelinite is Aphanitic whereas that of Basaltic Trachyandesite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular. Nephelinite appears Skeletal and Basaltic Trachyandesite appears Dull and Soft. The luster of Nephelinite is vitreous to metallic while that of Basaltic Trachyandesite is . Nephelinite is available in black, brown, green, grey, white colors whereas Basaltic Trachyandesite is available in black, brown, light to dark grey colors. The commercial uses of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo) and that of Basaltic Trachyandesite are an oil and gas reservoir, commemorative tablets, creating artwork.