1 Definition
1.1 Definition
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
1.2 History
1.2.1 Origin
1.2.2 Discoverer
1.3 Etymology
From Cornish gossen from gos, blood from Old Cornish guit
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
1.4 Class
Metamorphic Rocks
Igneous Rocks
1.4.1 Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
2 Texture
2.1 Texture
2.2 Color
Brown, Brown- Black, Gold, Green, Rust
Black, Brown, Colourless, Green, Grey, Red, Rust, White
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Decorative Aggregates, Interior Decoration
3.1.2 Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Garden Decoration, Paving Stone
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Construction Aggregate
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
3.4 Other Uses
3.4.1 Commercial Uses
Cemetery Markers, Commemorative Tablets, Gemstone
Creating Artwork, Gemstone, Jewelry
4 Types
4.1 Types
Translocated gossan and Leakage gossan
Rhomb Porphyry
4.2 Features
Clasts are smooth to touch, Easily splits into thin plates
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Not Applicable
Data Not Available
4.3.3 Sculpture
4.3.4 Famous Sculptures
Not Applicable
Data Not Available
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 Formation
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
Porphyry is formed in two stages: the magma cools slowly deep within the crust or the magma is cools rapidly as it erupts from a volcano, creating small grains that are usually invisible to naked eye.
5.2 Composition
5.2.1 Mineral Content
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
5.2.2 Compound Content
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
5.3.3 Weathering
5.3.4 Types of Weathering
Not Applicable
Biological Weathering, Chemical Weathering, Not Registered
5.3.5 Erosion
5.3.6 Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Fine to Medium Grained
Fine Grained
6.1.3 Fracture
6.1.4 Streak
6.1.5 Porosity
Highly Porous
Less Porous
6.1.6 Luster
6.1.7 Compressive Strength
6.1.8 Cleavage
6.1.9 Toughness
6.1.10 Specific Gravity
6.1.11 Transparency
Opaque
Translucent to Opaque
6.1.12 Density
Not Available2.5-2.52 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
China, India, Indonesia, Russia, Singapore, South Korea
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
7.1.2 Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Egypt, Ethiopia, Ghana, South Africa
7.1.3 Europe
Albania, France, Germany, Great Britain, United Kingdom
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
7.1.4 Others
7.2 Deposits in Western Continents
7.2.1 North America
Canada, USA
Canada, Cuba, Jamaica, USA
7.2.2 South America
Brazil, Colombia, Ecuador
Bolivia, Brazil, Colombia, Ecuador, Paraguay
7.3 Deposits in Oceania Continent
7.3.1 Australia
New South Wales, South Australia, Western Australia
New South Wales, New Zealand, Western Australia