Definition
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Arkose is a sedimentary rock, specifically a type of sandstone containing at least 25% feldspar
Discoverer
Cornish Gossen
Alexandre Brongniart
Etymology
From Cornish gossen from gos, blood from Old Cornish guit
From Auvergne region of France used by a French geologist Alexandre Brongniart in 1826 who applied this term to some feldspathic sandstones
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Rough, Sandy
Clastic
Color
Brown, Brown- Black, Gold, Green, Rust
Reddish Brown
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Banded
Rough and Dull
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Paving Stone, Office Buildings
Other Architectural Uses
Curbing
Whetstones
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Cement Manufacture, Construction Aggregate, for Road Aggregate, Production of Glass and Ceramics, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts
Artifacts, Sculpture, Small Figurines
Commercial Uses
Cemetery Markers, Commemorative Tablets, Gemstone
In aquifers, Soil Conditioner, Source of Magnesia (MgO), Tombstones
Types
Translocated gossan and Leakage gossan
Arkose
Features
Clasts are smooth to touch, Easily splits into thin plates
Available in Lots of Colors and Patterns, Generally rough to touch, Is one of the oldest rock
Archaeological Significance
Formation
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
Arkose rock forms from the weathering of feldspar-rich igneous or metamorphic rock, most commonly granitic rocks, which are primarily composed of quartz and feldspar.
Mineral Content
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz
Compound Content
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
-
-
Types of Weathering
-
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Grain Size
Fine to Medium Grained
Coarse Grained
Fracture
Conchoidal
Conchoidal
Streak
White to Grey
White
Porosity
Highly Porous
Highly Porous
Transparency
Opaque
Opaque
Density
-9999 g/cm3
-9999 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Indonesia, Russia, Singapore, South Korea
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Namibia, Nigeria, South Africa
Europe
Albania, France, Germany, Great Britain, United Kingdom
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil, Colombia, Ecuador
Brazil
Deposits in Oceania Continent
Australia
New South Wales, South Australia, Western Australia
New South Wales, New Zealand