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
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
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, 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
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
-
Konark Sun Temple in India, Washington Monument, US
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
-
Biological Weathering, Mechanical Weathering
Types of Erosion
-
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
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
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
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
All about Skarn and Gneiss Properties
Know all about Skarn and Gneiss properties here. All properties of rocks are important as they define the type of rock and its application. Skarn and Gneiss belong to Metamorphic Rocks.Texture of Skarn is Earthy, Mud-rich, Rough whereas that of Gneiss is Banded, Foliated, Platy. Skarn appears Dull and Gneiss appears Foliated. The luster of Skarn is waxy and dull while that of Gneiss is dull. Skarn is available in black, brown, green, grey, white colors whereas Gneiss is available in black, brown, pink, red, white colors. The commercial uses of Skarn are creating artwork, gemstone, jewelry, metallurgical flux, source of magnesia (mgo) and that of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums.