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
  
History
  
  
Origin
Indonesia
  
USA
  
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
  
Family
  
  
Group
Not Applicable
  
Not Applicable
  
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
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
No
  
Stain Resistant
Yes
  
No
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Dull and Banded
  
Dull, Banded and Foilated
  
Architecture
  
  
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
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
  
Manufacture of Magnesium and Dolomite Refractories
  
Medical Industry
Not Yet Used
  
Taken as a Supplement for Calcium or Magnesium
  
Antiquity Uses
Artifacts
  
Artifacts, Jewellery, Monuments, Sculpture
  
Other Uses
  
  
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
  
Not Available
  
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
  
Christ the Redeemer in Rio de Janeiro, Stonehenge in English county of Wiltshire
  
Sculpture
Not Yet Used
  
Used
  
Famous Sculptures
Not Applicable
  
Data Not Available
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Absent
  
Absent
  
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.
  
Composition
  
  
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
  
Transformation
  
  
Metamorphism
No
  
Yes
  
Types of Metamorphism
Not Applicable
  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Weathering
No
  
No
  
Types of Weathering
Not Applicable
  
Not Applicable
  
Erosion
Yes
  
No
  
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
  
Not Applicable
  
Physical Properties
  
  
Hardness
4-5
  
1
  
Grain Size
Fine to Medium Grained
  
Fine Grained
  
Fracture
Conchoidal
  
Conchoidal
  
Streak
White to Grey
  
Black
  
Porosity
Highly Porous
  
Less Porous
  
Luster
Metallic
  
Greasy
  
Compressive Strength
Not Available
  
225.00 N/mm
2
  
7
Cleavage
Not Available
  
Perfect
  
Toughness
Not Available
  
1
  
Specific Gravity
2.0
  
2.86
  
Transparency
Opaque
  
Opaque
  
Density
Not Available
  
2.8-2.9 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.24 kJ/Kg K
  
24
0.88 kJ/Kg K
  
13
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
  
Others
Not Yet Found
  
Not Yet Found
  
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