Definition
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Discoverer
Unknown
Cornish Gossen
Etymology
from French néphéline, from Greek nephelē
From Cornish gossen from gos, blood from Old Cornish guit
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Aphanitic
Rough, Sandy
Color
Black, Brown, Green, Grey, White
Brown, Brown- Black, Gold, Green, Rust
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Skeletal
Dull and Banded
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Commercial Uses
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Cemetery Markers, Commemorative Tablets, Gemstone
Types
Peralkaline Nephelinite
Translocated gossan and Leakage gossan
Features
Host Rock for Lead
Clasts are smooth to touch, Easily splits into thin plates
Archaeological Significance
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.
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
Mineral Content
Clinopyroxene, Nepheline, Plagioclase
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Compound Content
Ca, CaO, Carbon, Cl, MgO
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Types of Metamorphism
Contact Metamorphism
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Grain Size
Fine Grained
Fine to Medium Grained
Streak
White
White to Grey
Porosity
Less Porous
Highly Porous
Luster
Vitreous to Metallic
Metallic
Specific Gravity
2.4-2.9
2.0
Transparency
Opaque
Opaque
Density
2.5-3 g/cm3
-9999 g/cm3
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Japan
China, India, Indonesia, Russia, Singapore, South Korea
Africa
Rwanda, Tanzania
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Europe
-
Albania, France, Germany, Great Britain, United Kingdom
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Colombia
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
-
New South Wales, South Australia, Western Australia
Nephelinite vs Gossan 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 Gossan characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Nephelinite and Properties of Gossan. Learn more about Nephelinite vs Gossan in the next section. The interior uses of Nephelinite include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Gossan include Countertops, Decorative aggregates and Interior decoration. Due to some exceptional properties of Nephelinite and Gossan, 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 Gossan include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate.
More about Nephelinite and Gossan
Here you can know more about Nephelinite and Gossan. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Nephelinite and Gossan consists of mineral content and compound content. The mineral content of Nephelinite includes Clinopyroxene, Nepheline, Plagioclase and mineral content of Gossan includes Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon. You can also check out the list of all Igneous Rocks. When we have to compare Nephelinite vs Gossan, the texture, color and appearance plays an important role in determining the type of rock. Nephelinite is available in black, brown, green, grey, white colors whereas, Gossan is available in brown, brown- black, gold, green, rust colors. Appearance of Nephelinite is Skeletal and that of Gossan is Dull and Banded. Properties of rock is another aspect for Nephelinite vs Gossan. The hardness of Nephelinite is 6.5 and that of Gossan is 4-5. The types of Nephelinite are Peralkaline Nephelinite whereas types of Gossan are Translocated gossan and Leakage gossan. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Nephelinite is white while that of Gossan is white to grey. The specific heat capacity of Nephelinite is 0.88 kJ/Kg K and that of Gossan is 0.24 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 Gossan is heat resistant, impact resistant, pressure resistant.