Definition
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Rapakivi Granite is a hornblende-biotite Granite containing large rounded crystals of orthoclase which are mantled with oligoclase
Origin
Indonesia
Finland, Europe
Discoverer
Cornish Gossen
Jakob Sederholm
Etymology
From Cornish gossen from gos, blood from Old Cornish guit
From Finnish Rapakivi which stands for crumbly rock
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
Coarse Grained Rock, Opaque Rock
Texture
Rough, Sandy
Granular, Phaneritic
Color
Brown, Brown- Black, Gold, Green, Rust
Black, Grey, Orange, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Banded
Veined or Pebbled
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Office Buildings, Paving Stone, Resorts
Other Architectural Uses
Curbing
Not Yet Used
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
As Dimension Stone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Cemetery Markers, Commemorative Tablets, Gemstone
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Laboratory bench tops, Tombstones
Types
Translocated gossan and Leakage gossan
Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite
Features
Clasts are smooth to touch, Easily splits into thin plates
Available in Lots of Colors and Patterns, It is One of the Oldest, Strongest and Hardest Rock
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.
Granite is an igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks
Mineral Content
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact 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, Water Erosion, Wind Erosion
Grain Size
Fine to Medium Grained
Large and Coarse Grained
Fracture
Conchoidal
Not Available
Streak
White to Grey
White
Porosity
Highly Porous
Less Porous
Luster
Metallic
Dull to Grainy with Sporadic parts Pearly and Vitreous
Compressive Strength
Not Available
Cleavage
Not Available
Not Available
Toughness
Not Available
Not Available
Specific Gravity
2.0
2.6-2.7
Transparency
Opaque
Opaque
Density
Not Available
2.6-2.8 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Russia, Singapore, South Korea
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Albania, France, Germany, Great Britain, United Kingdom
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic, Venezuela
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil, Colombia, Ecuador
Not Yet Found
Deposits in Oceania Continent
Australia
New South Wales, South Australia, Western Australia
Not Yet Found