Definition
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
  
Rapakivi Granite is a hornblende-biotite Granite containing large rounded crystals of orthoclase which are mantled with oligoclase
  
History
  
  
Origin
Brazil
  
Finland, Europe
  
Discoverer
Unknown
  
Jakob Sederholm
  
Etymology
from French néphéline, from Greek nephelē
  
From Finnish Rapakivi which stands for crumbly rock
  
Class
Igneous Rocks
  
Igneous Rocks
  
Sub-Class
Durable Rock, Hard Rock
  
Durable Rock, Hard Rock
  
Family
  
  
Group
Plutonic
  
Plutonic
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Coarse Grained Rock, Opaque Rock
  
Texture
Aphanitic
  
Granular, Phaneritic
  
Color
Black, Brown, Colourless, Green, Grey, White
  
Black, Grey, Orange, Pink, White
  
Maintenance
Less
  
More
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
Yes
  
Yes
  
Wind Resistant
Yes
  
No
  
Acid Resistant
Yes
  
Yes
  
Appearance
Skeletal
  
Veined or Pebbled
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
  
Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
  
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
  
As Building Stone, As Facing Stone, Office Buildings, Paving Stone, Resorts
  
Other Architectural Uses
Curbing
  
Not Yet Used
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
  
As Dimension Stone
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
  
Artifacts, Monuments, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
  
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Laboratory bench tops, Tombstones
  
Types
Peralkaline Nephelinite
  
Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite
  
Features
Host Rock for Lead
  
Available in Lots of Colors and Patterns, It is One of the Oldest, Strongest and Hardest Rock
  
Archaeological Significance
  
  
Monuments
Used
  
Used
  
Famous Monuments
Data Not Available
  
Data Not Available
  
Sculpture
Used
  
Used
  
Famous Sculptures
Data Not Available
  
Data Not Available
  
Pictographs
Not Used
  
Not Used
  
Petroglyphs
Not Used
  
Not Used
  
Figurines
Used
  
Used
  
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.
  
Granite is an igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks
  
Composition
  
  
Mineral Content
Clinopyroxene, Nepheline, Plagioclase
  
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
  
Compound Content
Ca, CaO, Carbon, Cl, MgO
  
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Contact Metamorphism
  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
  
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
6.5
  
6-7
  
Grain Size
Fine Grained
  
Large and Coarse Grained
  
Fracture
Flat
  
Not Available
  
Streak
White
  
White
  
Porosity
Less Porous
  
Less Porous
  
Luster
Vitreous to Metallic
  
Dull to Grainy with Sporadic parts Pearly and Vitreous
  
Compressive Strength
35.00 N/mm2
  
29
175.00 N/mm2
  
13
Cleavage
Imperfect
  
Not Available
  
Toughness
2.7
  
Not Available
  
Specific Gravity
2.4-2.9
  
2.6-2.7
  
Transparency
Opaque
  
Opaque
  
Density
2.5-3 g/cm3
  
2.6-2.8 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.88 kJ/Kg K
  
13
0.79 kJ/Kg K
  
16
Resistance
Heat Resistant
  
Heat 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
  
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic, Venezuela
  
Others
Hawaii Islands
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
Canada, USA
  
South America
Colombia
  
Not Yet Found
  
Deposits in Oceania Continent
  
  
Australia
Not Yet Found
  
Not Yet Found
  
Nephelinite vs Rapakivi Granite Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Nephelinite vs Rapakivi Granite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Nephelinite and Properties of Rapakivi Granite. Learn more about Nephelinite vs Rapakivi Granite in the next section. The interior uses of Nephelinite include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Rapakivi Granite include Bathrooms, Countertops, Decorative aggregates, Entryways, Floor tiles, Flooring, Homes, Hotels, Interior decoration, Kitchens and Stair treads. Due to some exceptional properties of Nephelinite and Rapakivi Granite, they have various applications in construction industry. The uses of Nephelinite in construction industry include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate and that of Rapakivi Granite include As dimension stone.
More about Nephelinite and Rapakivi Granite
Here you can know more about Nephelinite and Rapakivi Granite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Nephelinite and Rapakivi Granite consists of mineral content and compound content. The mineral content of Nephelinite includes Clinopyroxene, Nepheline, Plagioclase and mineral content of Rapakivi Granite includes Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Nephelinite vs Rapakivi Granite, the texture, color and appearance plays an important role in determining the type of rock. Nephelinite is available in black, brown, colourless, green, grey, white colors whereas, Rapakivi Granite is available in black, grey, orange, pink, white colors. Appearance of Nephelinite is Skeletal and that of Rapakivi Granite is Veined or Pebbled. Properties of rock is another aspect for Nephelinite vs Rapakivi Granite. The hardness of Nephelinite is 6.5 and that of Rapakivi Granite is 6-7. The types of Nephelinite are Peralkaline Nephelinite whereas types of Rapakivi Granite are Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Nephelinite and Rapakivi Granite is white. The specific heat capacity of Nephelinite is 0.88 kJ/Kg K and that of Rapakivi Granite is 0.79 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Nephelinite is heat resistant whereas Rapakivi Granite is heat resistant, wear resistant.