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