Definition
Anorthosite is a granular igneous rock composed largely of labradorite or plagioclase
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Discoverer
Unknown
Cornish Gossen
Etymology
From French anorthose plagioclase + -ite1
From Cornish gossen from gos, blood from Old Cornish guit
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Foliated, Glassy
Rough, Sandy
Color
Black, Bluish - Grey, Brown, Green, Grey, Light Greenish Grey, Pink, White
Brown, Brown- Black, Gold, Green, Rust
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Dull and Banded
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts
Commercial Uses
Creating Artwork, Curling
Cemetery Markers, Commemorative Tablets, Gemstone
Types
Proterozoic Anorthosite and Archean Anorthosite
Translocated gossan and Leakage gossan
Features
Generally rough to touch, Is one of the oldest rock
Clasts are smooth to touch, Easily splits into thin plates
Archaeological Significance
Formation
Anorthosite is a phaneritic, intrusive igneous rock which is characterized by a predominance of plagioclase feldspar which is almost 90–100%, and a minimal mafic component.
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
Mineral Content
Amphibole, Clinopyroxene, Ilmenite, Magnetite, Olivine, Orthopyroxene
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Compound Content
Ca, CaO, Chromium(III) Oxide, MgO, Sulfur Trioxide
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism
-
Types of Weathering
Biological Weathering
-
Types of Erosion
Chemical Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Grain Size
Coarse Grained
Fine to Medium Grained
Fracture
Irregular
Conchoidal
Streak
White
White to Grey
Porosity
Less Porous
Highly Porous
Luster
Pearly to Subvitreous
Metallic
Specific Gravity
2.62-2.82
2.0
Transparency
Translucent
Opaque
Density
2.7-4 g/cm3
-9999 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
-
China, India, Indonesia, Russia, Singapore, South Korea
Africa
-
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Europe
Bulgaria, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Malta, Poland, Portugal, Romania, Slovenia, Spain, Sweden, The Czech Republic
Albania, France, Germany, Great Britain, United Kingdom
Deposits in Western Continents
North America
Canada
Canada, USA
South America
Bolivia, Colombia
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
Central Australia, South Australia, Western Australia
New South Wales, South Australia, Western Australia
All about Anorthosite and Gossan Properties
Know all about Anorthosite and Gossan properties here. All properties of rocks are important as they define the type of rock and its application. Anorthosite belongs to Igneous Rocks while Gossan belongs to Metamorphic Rocks.Texture of Anorthosite is Foliated, Glassy whereas that of Gossan is Rough, Sandy. Anorthosite appears Layered, Banded, Veined and Shiny and Gossan appears Dull and Banded. The luster of Anorthosite is pearly to subvitreous while that of Gossan is metallic. Anorthosite is available in black, bluish - grey, brown, green, grey, light greenish grey, pink, white colors whereas Gossan is available in brown, brown- black, gold, green, rust colors. The commercial uses of Anorthosite are creating artwork, curling and that of Gossan are cemetery markers, commemorative tablets, gemstone.