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
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Discoverer
Tornebohm
Unknown
Etymology
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
From German Grauwacke, from grau grey + wacke
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Earthy, Mud-rich, Rough
Clastic
Color
Black, Brown, Green, Grey, White
Beige, Black, Brown, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Decorative Aggregates, Floor Tiles, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing, Whetstones
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
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
Types
Endoskarns
Greywacke
Features
Host Rock for Lead, Zinc and Copper Deposits
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Archaeological Significance
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.
Graywacke rock is a type of sedimentary rock, which is also known as immature sandstone, which is indurated, dark grey and consisting of poorly sorted angular to sub-angular, sand-sized grains.
Mineral Content
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Aluminium Oxide, NaCl, CaO, Chromium(III) Oxide, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
-
Types of Weathering
-
Biological Weathering, Chemical Weathering
Types of Erosion
-
Coastal Erosion, Sea Erosion, Wind Erosion
Grain Size
Fine Grained
Angular and Fine
Fracture
Irregular
Conchoidal
Streak
Light to dark brown
White
Porosity
Less Porous
Highly Porous
Luster
Waxy and Dull
Dull
Specific Gravity
2.86
2.2-2.8
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
2.6-2.61 g/cm3
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
South Africa, Western Africa
Namibia, Nigeria, South Africa
Europe
United Kingdom
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Deposits in Western Continents
North America
Canada
Canada, USA
South America
Brazil, Colombia, Paraguay
Brazil
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New South Wales, New Zealand
All about Skarn and Greywacke Properties
Know all about Skarn and Greywacke properties here. All properties of rocks are important as they define the type of rock and its application. Skarn belongs to Metamorphic Rocks while Greywacke belongs to Sedimentary Rocks.Texture of Skarn is Earthy, Mud-rich, Rough whereas that of Greywacke is Clastic. Skarn appears Dull and Greywacke appears Dull. The luster of Skarn is waxy and dull while that of Greywacke is dull. Skarn is available in black, brown, green, grey, white colors whereas Greywacke is available in beige, black, brown, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors. The commercial uses of Skarn are creating artwork, gemstone, jewelry, metallurgical flux, source of magnesia (mgo) and that of Greywacke are as armour rock for sea walls, petroleum reservoirs, sea defence, tombstones.