Definition
Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks
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 the Middle High German verb gneist (to spark; so called because the rock glitters)
From Cornish gossen from gos, blood from Old Cornish guit
Class
Metamorphic Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Not Applicable
Other Categories
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Banded, Foliated, Platy
Rough, Sandy
Color
Black, Brown, Pink, Red, White
Brown, Brown- Black, Gold, Green, Rust
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Foliated
Dull and Banded
Interior Uses
Countertops, Decorative Aggregates, Flooring, Interior Decoration
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts
Commercial Uses
Cemetery Markers, Jewelry, Tombstones, Used in aquariums
Cemetery Markers, Commemorative Tablets, Gemstone
Types
Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.
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
Monuments
Used
Not Yet Used
Famous Monuments
Konark Sun Temple in India, Washington Monument, US
Not Applicable
Sculpture
Not Yet Used
Not Yet Used
Famous Sculptures
Not Applicable
Not Applicable
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Figurines
Not Yet Used
Not Yet Used
Formation
Gneiss is a high grade metamorphic rock i.e. it has been subjected to higher temperatures and pressures than schist. It is formed by the metamorphosis of Gneiss forms from volcanic rock, shale or granitie.
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
Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Compound Content
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Types of Metamorphism
Impact Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Mechanical Weathering
Not Applicable
Types of Erosion
Chemical Erosion, Coastal Erosion, Sea Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Grain Size
Medium to Coarse Grained
Fine to Medium Grained
Fracture
Irregular
Conchoidal
Streak
White
White to Grey
Porosity
Very Less Porous
Highly Porous
Compressive Strength
Not Available
Cleavage
Poor
Not Available
Toughness
1.2
Not Available
Specific Gravity
2.5-2.7
2.0
Transparency
Translucent to Opaque
Opaque
Density
2.6-2.9 g/cm3
Not Available
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia
China, India, Indonesia, Russia, Singapore, South Korea
Africa
Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Europe
Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine, United Kingdom
Albania, France, Germany, Great Britain, United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, Costa Rica, Cuba, Mexico, Panama, USA
Canada, USA
South America
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria
New South Wales, South Australia, Western Australia
Gneiss vs Gossan Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Gneiss vs Gossan characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Gneiss and Properties of Gossan. Learn more about Gneiss vs Gossan in the next section. The interior uses of Gneiss include Countertops, Decorative aggregates, Flooring and Interior decoration whereas the interior uses of Gossan include Countertops, Decorative aggregates and Interior decoration. Due to some exceptional properties of Gneiss and Gossan, they have various applications in construction industry. The uses of Gneiss in construction industry include As dimension stone and that of Gossan include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate.
More about Gneiss and Gossan
Here you can know more about Gneiss and Gossan. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Gneiss and Gossan consists of mineral content and compound content. The mineral content of Gneiss includes Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon and mineral content of Gossan includes Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon. You can also check out the list of all Metamorphic Rocks. When we have to compare Gneiss vs Gossan, the texture, color and appearance plays an important role in determining the type of rock. Gneiss is available in black, brown, pink, red, white colors whereas, Gossan is available in brown, brown- black, gold, green, rust colors. Appearance of Gneiss is Foliated and that of Gossan is Dull and Banded. Properties of rock is another aspect for Gneiss vs Gossan. The hardness of Gneiss is 7 and that of Gossan is 4-5. The types of Gneiss are Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss. whereas types of Gossan are Translocated gossan and Leakage gossan. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Gneiss is white while that of Gossan is white to grey. The specific heat capacity of Gneiss is Not Available and that of Gossan is 0.24 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Gneiss is heat resistant, pressure resistant, scratch resistant, wear resistant whereas Gossan is heat resistant, impact resistant, pressure resistant.