Definition
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
Discoverer
Cornish Gossen
Unknown
Etymology
From Cornish gossen from gos, blood from Old Cornish guit
from French néphéline, from Greek nephelē
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Group
Not Applicable
Plutonic
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Rough, Sandy
Aphanitic
Color
Brown, Brown- Black, Gold, Green, Rust
Black, Brown, Colourless, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Banded
Skeletal
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, 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, Cement Manufacture, Construction Aggregate, for Road Aggregate
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Cemetery Markers, Commemorative Tablets, Gemstone
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Types
Translocated gossan and Leakage gossan
Peralkaline Nephelinite
Features
Clasts are smooth to touch, Easily splits into thin plates
Host Rock for Lead
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Figurines
Not Yet Used
Used
Formation
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
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
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Clinopyroxene, Nepheline, Plagioclase
Compound Content
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Ca, CaO, Carbon, Cl, MgO
Types of Metamorphism
Not Applicable
Contact Metamorphism
Types of Weathering
Not Applicable
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Fine to Medium Grained
Fine Grained
Streak
White to Grey
White
Porosity
Highly Porous
Less Porous
Luster
Metallic
Vitreous to Metallic
Compressive Strength
Not Available
Cleavage
Not Available
Imperfect
Toughness
Not Available
2.7
Specific Gravity
2.0
2.4-2.9
Transparency
Opaque
Opaque
Density
Not Available
2.5-3 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Russia, Singapore, South Korea
Japan
Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Rwanda, Tanzania
Europe
Albania, France, Germany, Great Britain, United Kingdom
Not Yet Found
Others
Not Yet Found
Hawaii Islands
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil, Colombia, Ecuador
Colombia
Deposits in Oceania Continent
Australia
New South Wales, South Australia, Western Australia
Not Yet Found
All about Gossan and Nephelinite Properties
Know all about Gossan and Nephelinite properties here. All properties of rocks are important as they define the type of rock and its application. Gossan belongs to Metamorphic Rocks while Nephelinite belongs to Igneous Rocks.Texture of Gossan is Rough, Sandy whereas that of Nephelinite is Aphanitic. Gossan appears Dull and Banded and Nephelinite appears Skeletal. The luster of Gossan is metallic while that of Nephelinite is vitreous to metallic. Gossan is available in brown, brown- black, gold, green, rust colors whereas Nephelinite is available in black, brown, colourless, green, grey, white colors. The commercial uses of Gossan are cemetery markers, commemorative tablets, gemstone and that of Nephelinite are creating artwork, soil conditioner, source of magnesia (mgo).