Definition
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Whiteschist is an uncommon rock type belonging to a class of metamorphic rock, this is formed at high-ultra-high pressures
History
Origin
Brazil
Tasmania
Discoverer
Unknown
Unknown
Etymology
from French néphéline, from Greek nephelē
From French schiste, Greek skhistos i.e. split
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
Family
Group
Plutonic
-
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Aphanitic
Foliated
Color
Black, Brown, Green, Grey, White
Green, Grey, White
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Skeletal
Banded and Foilated
Architecture
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
for Road Aggregate
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Other Uses
Commercial Uses
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Creating Artwork, Gemstone, Jewelry, Production of Lime
Types
Peralkaline Nephelinite
-
Features
Host Rock for Lead
High percentage of mica, Host Rock for Lead
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
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.
Whiteschist is formed by dynamic metamorphism at high temperatures and pressures that aligns the grains of mica, hornblende and other elongated minerals into thin layers.
Composition
Mineral Content
Clinopyroxene, Nepheline, Plagioclase
Carbonate, Coesite, Quartz, Silica
Compound Content
Ca, CaO, Carbon, Cl, MgO
CaO, Mg, MgO, Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Contact Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Physical Properties
Hardness
6.51.5
1
7
👆🏻
Grain Size
Fine Grained
Fine to Medium Grained
Fracture
Flat
Conchoidal
Streak
White
White
Porosity
Less Porous
Less Porous
Luster
Vitreous to Metallic
Subvitreous to Dull
Compressive Strength
35.00 N/mm2200.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Perfect
Toughness
2.7
1
Specific Gravity
2.4-2.92.86
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.5-3 g/cm32.8-2.9 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.88 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Japan
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
Africa
Rwanda, Tanzania
Egypt, Ethiopia, Morocco, Nigeria, South Africa
Europe
-
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Others
Hawaii Islands
-
Deposits in Western Continents
North America
Canada, USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
Colombia
Brazil, Colombia, Guyana
Deposits in Oceania Continent
Australia
-
New South Wales, New Zealand, Queensland