Definition
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Vogesite is a porphyritic alkaline igneous rock and is a variety of Lamprophyre which is dominated by essential amphibole, usually hornblende, and potassic feldspar
Discoverer
Cornish Gossen
Unknown
Etymology
From Cornish gossen from gos, blood from Old Cornish guit
From the variety of Lamprophyre Greek lampros bright and shining + porphureos purple
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Plutonic
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Texture
Rough, Sandy
Porphyritic
Color
Brown, Brown- Black, Gold, Green, Rust
Black, Bluish - Grey, Brown, Dark Greenish - Grey, Green, Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Banded
Dull, Banded and Foilated
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Decorative Aggregates, Entryways, Flooring, 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, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
Not Yet Used
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Gemstone
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO)
Types
Translocated gossan and Leakage gossan
Minette, Alnoite, Camptonite, Monchiquite, Fourchite, Vogesite, Appinite and Spessartite
Features
Clasts are smooth to touch, Easily splits into thin plates
Always found as volcanic pipes over deep continental crust, Host rock for Diamond, Is one of the oldest rock, Surfaces are often shiny
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
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.
Vogesite formation takes place deep beneath the Earth’s surface at around 150 to 450 kilometres, and are erupted rapidly and violently.
Mineral Content
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Amphibole, Carbonate, Garnet, Micas, Olivine, Phlogopite, Pyroxene
Compound Content
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Not Applicable
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Fine to Medium Grained
Fine to Coarse Grained
Fracture
Conchoidal
Conchoidal
Streak
White to Grey
White
Porosity
Highly Porous
Very Less Porous
Luster
Metallic
Subvitreous to Dull
Cleavage
Not Available
Conchoidal
Toughness
Not Available
Not Available
Specific Gravity
2.0
2.86-2.87
Transparency
Opaque
Translucent to Opaque
Density
Not Available
2.95-2.96 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Russia, Singapore, South Korea
Russia
Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Angola, Botswana, Cameroon, Ethiopia, South Africa
Europe
Albania, France, Germany, Great Britain, United Kingdom
England, Hungary, Iceland, United Kingdom
Others
Not Yet Found
Antarctica, Greenland
Deposits in Western Continents
North America
Canada, USA
Canada, Mexico, USA
South America
Brazil, Colombia, Ecuador
Argentina, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New South Wales, South Australia, Western Australia
New South Wales, New Zealand, Queensland, South Australia, Western Australia