Definition
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
History
Origin
Brazil
Discoverer
Unknown
Etymology
from French néphéline, from Greek nephelē
Class
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Family
Group
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Texture
Aphanitic
Color
Black, Brown, Green, Grey, White
Maintenance
Less
Durability
Durable
Water Resistant
✔
✘
81% - Igneous Rocks Rocks have it !
Scratch Resistant
✔
✘
86% - Igneous Rocks Rocks have it !
Stain Resistant
✔
✘
66% - Igneous Rocks Rocks have it !
Wind Resistant
✔
✘
49% - Igneous Rocks Rocks have it !
Acid Resistant
✔
✘
48% - Igneous Rocks Rocks have it !
Appearance
Skeletal
Architecture
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Industry
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Other Uses
Commercial Uses
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Types
Peralkaline Nephelinite
Features
Host Rock for Lead
Archaeological Significance
Monuments
-
Famous Monuments
-
Sculpture
-
Famous Sculptures
-
Pictographs
-
Petroglyphs
-
Figurines
-
Fossils
Absent
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.
Composition
Mineral Content
Clinopyroxene, Nepheline, Plagioclase
Compound Content
Ca, CaO, Carbon, Cl, MgO
Transformation
Metamorphism
✔
✘
97% - Igneous Rocks Rocks have it !
Types of Metamorphism
Contact Metamorphism
Weathering
✔
✘
99% - Igneous Rocks Rocks have it !
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
92% - Igneous Rocks Rocks have it !
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
6.5
1
7
👆🏻
Grain Size
Fine Grained
Fracture
Flat
Streak
White
Porosity
Less Porous
Luster
Vitreous to Metallic
Compressive Strength
35.00 N/mm2
Rank: 43 (Overall)
0.15
450
👆🏻
Cleavage
-
Toughness
2.7
Specific Gravity
2.4-2.9
0
8.4
👆🏻
Transparency
Opaque
Density
2.5-3 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.88 kJ/Kg K
Rank: 13 (Overall)
0.14
3.2
👆🏻
Resistance
Heat Resistant
Deposits in Eastern Continents
Asia
Japan
Africa
Rwanda, Tanzania
Europe
-
Others
Hawaii Islands
Deposits in Western Continents
North America
Canada, USA
South America
Colombia
Deposits in Oceania Continent
Australia
-