Definition
Variolites are a group of dark green basic igneous rocks which exhibit pale colored spots, or spherules, especially on weathered surfaces, that give them a pockmarked appearance
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Discoverer
Unknown
Unknown
Etymology
From Latin varius, speckled, variegated
from French néphéline, from Greek nephelē
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Aphanitic
Color
Black, Brown, Light to Dark Grey
Black, Brown, Colourless, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Skeletal
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Cemetery Markers, Creating Artwork
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Types
Not Available
Peralkaline Nephelinite
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Host Rock for Lead
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Formation
Variolites are a group of dark green basic igneous rocks that exhibit pale colored spots on weathered surfaces that give them a pockmarked appearance.
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
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Not Applicable
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Not Applicable
Fine Grained
Streak
White to Grey
White
Porosity
Less Porous
Less Porous
Luster
Not Available
Vitreous to Metallic
Cleavage
Not Available
Imperfect
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
Europe
Iceland
Not Yet Found
Others
Not Yet Found
Hawaii Islands
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Colombia
Deposits in Oceania Continent
Australia
Not Yet Found
Not Yet Found
All about Variolite and Nephelinite Properties
Know all about Variolite and Nephelinite properties here. All properties of rocks are important as they define the type of rock and its application. Variolite and Nephelinite belong to Igneous Rocks.Texture of Variolite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular whereas that of Nephelinite is Aphanitic. Variolite appears Dull and Soft and Nephelinite appears Skeletal. The luster of Variolite is not available while that of Nephelinite is vitreous to metallic. Variolite is available in black, brown, light to dark grey colors whereas Nephelinite is available in black, brown, colourless, green, grey, white colors. The commercial uses of Variolite are cemetery markers, creating artwork and that of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo).