Definition
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Discoverer
Unknown
Alexandre Brongniart and René Just Haüy
Etymology
from French néphéline, from Greek nephelē
From Greek trakhus rough’ or trakhutēs roughness
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
Aphanitic to Porphyritic
Color
Black, Brown, Colourless, Green, Grey, White
Black, Brown, Dark Greenish - Grey, Green, Grey, Light to Dark Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Skeletal
Banded
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Cemetery Markers, Creating Artwork
Types
Peralkaline Nephelinite
Not Available
Features
Host Rock for Lead
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
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.
Trachyte is an igneous volcanic rock with an aphanitic to porphyritic texture. It is the volcanic equivalent of syenite rock and forms as a result of magmatic differentiation.
Mineral Content
Clinopyroxene, Nepheline, Plagioclase
Augite, Biotite, Feldspar, Hornblade, Plagioclase, Quartz
Compound Content
Ca, CaO, Carbon, Cl, MgO
Potassium Oxide, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
Contact Metamorphism
Cataclastic Metamorphism, Contact 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
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Fine Grained
Fracture
Flat
Not Available
Porosity
Less Porous
Less Porous
Luster
Vitreous to Metallic
Metallic
Cleavage
Imperfect
Not Available
Toughness
2.7
Not Available
Specific Gravity
2.4-2.9
2.7
Transparency
Opaque
Opaque
Density
2.5-3 g/cm3
2.43-2.45 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Japan
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
Rwanda, Tanzania
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Not Yet Found
Bulgaria, England, Germany, Norway, Romania, Switzerland
Others
Hawaii Islands
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
USA
South America
Colombia
Brazil, Chile
Deposits in Oceania Continent
Australia
Not Yet Found
New Zealand, Queensland, South Australia, Western Australia
All about Nephelinite and Trachyte Properties
Know all about Nephelinite and Trachyte properties here. All properties of rocks are important as they define the type of rock and its application. Nephelinite and Trachyte belong to Igneous Rocks.Texture of Nephelinite is Aphanitic whereas that of Trachyte is Aphanitic to Porphyritic. Nephelinite appears Skeletal and Trachyte appears Banded. The luster of Nephelinite is vitreous to metallic while that of Trachyte is metallic. Nephelinite is available in black, brown, colourless, green, grey, white colors whereas Trachyte is available in black, brown, dark greenish - grey, green, grey, light to dark grey, white colors. The commercial uses of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo) and that of Trachyte are cemetery markers, creating artwork.