Definition
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
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
Origin
USA, Australia
Unknown
Discoverer
Tornebohm
Unknown
Etymology
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
From the Middle High German verb gneist (to spark; so called because the rock glitters)
Class
Metamorphic Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Earthy, Mud-rich, Rough
Banded, Foliated, Platy
Color
Black, Brown, Colourless, Green, Grey, White
Black, Brown, Pink, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Countertops, Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
As Dimension Stone
Medical Industry
Not Applicable
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts
Commercial Uses
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Cemetery Markers, Jewelry, Tombstones, Used in aquariums
Types
Endoskarns
Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.
Features
Host Rock for Lead, Zinc and Copper Deposits
Generally rough to touch, Is one of the oldest rock
Archaeological Significance
Famous Monuments
Data Not Available
Konark Sun Temple in India, Washington Monument, US
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Figurines
Used
Not Yet Used
Formation
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
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.
Mineral Content
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon
Compound Content
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Impact Metamorphism
Types of Weathering
Not Applicable
Biological Weathering, Mechanical Weathering
Types of Erosion
Not Applicable
Chemical Erosion, Coastal Erosion, Sea Erosion
Grain Size
Fine Grained
Medium to Coarse Grained
Fracture
Irregular
Irregular
Streak
Light to dark brown
White
Porosity
Less Porous
Very Less Porous
Luster
Waxy and Dull
Dull
Compressive Strength
Not Available
Specific Gravity
2.86
2.5-2.7
Transparency
Opaque
Translucent to Opaque
Density
2.8-2.9 g/cm3
2.6-2.9 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant
Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia
Africa
South Africa, Western Africa
Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo
Europe
United Kingdom
Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine, United Kingdom
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
Brazil, Colombia, Paraguay
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New South Wales, New Zealand, Queensland, Victoria
Skarn vs Gneiss 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. Skarn vs Gneiss characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Skarn and Properties of Gneiss. Learn more about Skarn vs Gneiss in the next section. The interior uses of Skarn include Decorative aggregates, Entryways and Interior decoration whereas the interior uses of Gneiss include Countertops, Decorative aggregates, Flooring and Interior decoration. Due to some exceptional properties of Skarn and Gneiss, they have various applications in construction industry. The uses of Skarn in construction industry include As a flux in the production of steel and pig iron, As a sintering agent in steel industry to process iron ore, As dimension stone, Gold and silver production, Manufacture of magnesium and dolomite refractories and that of Gneiss include As dimension stone.
More about Skarn and Gneiss
Here you can know more about Skarn and Gneiss. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Skarn and Gneiss consists of mineral content and compound content. The mineral content of Skarn includes Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite and mineral content of Gneiss includes Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon. You can also check out the list of all Metamorphic Rocks. When we have to compare Skarn vs Gneiss, the texture, color and appearance plays an important role in determining the type of rock. Skarn is available in black, brown, colourless, green, grey, white colors whereas, Gneiss is available in black, brown, pink, red, white colors. Appearance of Skarn is Dull and that of Gneiss is Foliated. Properties of rock is another aspect for Skarn vs Gneiss. The hardness of Skarn is 6.5 and that of Gneiss is 7. The types of Skarn are Endoskarns whereas types of Gneiss are Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Skarn is light to dark brown while that of Gneiss is white. The specific heat capacity of Skarn is 0.92 kJ/Kg K and that of Gneiss is Not Available. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Skarn is heat resistant whereas Gneiss is heat resistant, pressure resistant, scratch resistant, wear resistant.