Definition
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
It is a metamorphic magnesium rich rock because it is composed of the mineral talc
Discoverer
Cornish Gossen
Unknown
Etymology
From Cornish gossen from gos, blood from Old Cornish guit
From 17th century, because of its greasy feel and use like a soap
Class
Metamorphic Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Rough, Sandy
Polished
Color
Brown, Brown- Black, Gold, Green, Rust
Black, Black to Grey, Green, Grey
Durability
Durable
Durable
Appearance
Dull and Banded
Dull, Banded and Foilated
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Bathrooms, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Facing Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Manufacture of Magnesium and Dolomite Refractories
Medical Industry
-
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts
Artifacts, Jewellery, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Gemstone
Cemetery Markers, Creating Artwork, Gemstone, Jewelry, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Production of Lime, Source of Magnesia (MgO)
Types
Translocated gossan and Leakage gossan
Metamorphic rock
Features
Clasts are smooth to touch, Easily splits into thin plates
Host Rock for Lead
Archaeological Significance
Famous Monuments
-
Christ the Redeemer in Rio de Janeiro, Stonehenge in English county of Wiltshire
Formation
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
Soapstone is a talc-schist, which is a type of metamorphic rock and it is largely composed of the mineral talc and is thus rich inmagnesium.
Mineral Content
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Albite, Apatite, Biotite, Calcite, Carbonate, Clay Minerals, Hornblende, Ilmenite, Micas, Plagioclase, Pyroxene, Quartz
Compound Content
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
CaO, Mg, MgO
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
-
Grain Size
Fine to Medium Grained
Fine Grained
Fracture
Conchoidal
Conchoidal
Streak
White to Grey
Black
Porosity
Highly Porous
Less Porous
Specific Gravity
2.0
2.86
Transparency
Opaque
Opaque
Density
-9999 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Russia, Singapore, South Korea
China, India, Indonesia, Japan, North Korea, Russia, Saudi Arabia, Singapore, South Korea, Sri Lanka, Tajikistan, Thailand
Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Egypt, Ethiopia, Ghana, South Africa, Western Africa
Europe
Albania, France, Germany, Great Britain, United Kingdom
Austria, England, Finland, France, Germany, Greece, Spain, Sweden, Switzerland, United Kingdom
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
Central Australia, New Zealand, Queensland
All about Gossan and Soapstone Properties
Know all about Gossan and Soapstone properties here. All properties of rocks are important as they define the type of rock and its application. Gossan and Soapstone belong to Metamorphic Rocks.Texture of Gossan is Rough, Sandy whereas that of Soapstone is Polished. Gossan appears Dull and Banded and Soapstone appears Dull, Banded and Foilated. The luster of Gossan is metallic while that of Soapstone is greasy. Gossan is available in brown, brown- black, gold, green, rust colors whereas Soapstone is available in black, black to grey, green, grey colors. The commercial uses of Gossan are cemetery markers, commemorative tablets, gemstone and that of Soapstone are cemetery markers, creating artwork, gemstone, jewelry, manufacture of soap, solvents, dyes, plastics and fibres, production of lime, source of magnesia (mgo).