Definition
Nepheline Syenite is a holocrystalline plutonic rock resembling syenite but containing nepheline and lacking quartz
Arkose is a sedimentary rock, specifically a type of sandstone containing at least 25% feldspar
Discoverer
Unknown
Alexandre Brongniart
Etymology
From origin of a Palaeozoic nepheline syenite from northern Shanxi Province, China
From Auvergne region of France used by a French geologist Alexandre Brongniart in 1826 who applied this term to some feldspathic sandstones
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Group
Plutonic
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Color
Brown, Buff, Cream, Green, Grey, Pink, White
Reddish Brown
Durability
Durable
Durable
Appearance
Banded and Foilated
Rough and Dull
Interior Uses
Countertops, Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Paving Stone, Office Buildings
Other Architectural Uses
Curbing
Whetstones
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories, Production of Glass and Ceramics
Cement Manufacture, Construction Aggregate, for Road Aggregate, Production of Glass and Ceramics, Raw material for the manufacture of mortar
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Sculpture, Small Figurines
Commercial Uses
Cemetery Markers, Creating Artwork
In aquifers, Soil Conditioner, Source of Magnesia (MgO), Tombstones
Types
Borolanite and Litchfieldite
Not Available
Features
Application of acids on the surface causes cloudy frosting, Available in Lots of Colors and Patterns, Dissolves in hydrochloric acid, Is one of the oldest rock
Available in Lots of Colors and Patterns, Generally rough to touch, Is one of the oldest rock
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Formation
Nepheline Syenites are formed due to alkaline igneous activities and are generally formed in thick continental crustal areas or in Cordilleran subduction zones.
Arkose rock forms from the weathering of feldspar-rich igneous or metamorphic rock, most commonly granitic rocks, which are primarily composed of quartz and feldspar.
Mineral Content
Albite, Amphibole, Biotite, Cancrinite, Feldspar, Hornblende, Plagioclase, Pyroxene, Sodalite
Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Impact Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Coarse Grained
Fracture
Conchoidal to Uneven
Conchoidal
Porosity
Less Porous
Highly Porous
Luster
Greasy to Dull
Dull
Compressive Strength
Not Available
Cleavage
Poor
Not Available
Toughness
Not Available
Not Available
Transparency
Translucent to Opaque
Opaque
Density
2.6 g/cm3
Not Available
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Indonesia, Iran, Russia, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Turkmenistan, Vietnam
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Namibia, Nigeria, South Africa
Europe
Andorra, Finland, France, Great Britain, Italy, Norway, Portugal, Spain, Sweden
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Others
Greenland
Greenland
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil, Chile, Colombia, Uruguay, Venezuela
Brazil
Deposits in Oceania Continent
Australia
New Zealand, Queensland, South Australia, Tasmania, Western Australia
New South Wales, New Zealand