Definition
Blueschist is a metamorphic rock which is generally blue in color and is formed under conditions of high pressure and low temperature
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
Origin
USA
USA, Australia
Discoverer
Edgar Bailey
Tornebohm
Etymology
From French schiste, Greek skhistos i.e. split
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
Class
Metamorphic Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated
Earthy, Mud-rich, Rough
Color
Blue, Bluish - Grey, Purple, Shades of Blue
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Appearance
Dull and Banded
Dull
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
-
Curbing
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
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
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Tombstones
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Types
Metamorphic rock
Endoskarns
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Host Rock for Lead, Zinc and Copper Deposits
Archaeological Significance
Formation
Blueschist forms due to the metamorphism of basalt and other rocks with similar composition at high pressures and low temperatures and approximately corresponding to a depth of 15 to 30 kilometers and 200 to 500 °C.
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.
Mineral Content
Albite, Chlorite, Epidote, Garnet, Glaucophane, Lawsonite, Muscovite or Illite, Quartz
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
-
Grain Size
Fine to Medium Grained
Fine Grained
Fracture
Conchoidal
Irregular
Streak
White to Grey
Light to dark brown
Porosity
Highly Porous
Less Porous
Luster
Dull
Waxy and Dull
Specific Gravity
3-3.2
2.86
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
2.8-2.9 g/cm3
Resistance
Impact Resistant, Pressure Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Japan, Turkey
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Africa
Egypt, Ethiopia, South Africa
South Africa, Western Africa
Europe
France, Greece, Iceland
United Kingdom
Deposits in Western Continents
South America
-
Brazil, Colombia, Paraguay
Deposits in Oceania Continent
Australia
New Zealand
Central Australia, Western Australia
All about Blueschist and Skarn Properties
Know all about Blueschist and Skarn properties here. All properties of rocks are important as they define the type of rock and its application. Blueschist and Skarn belong to Metamorphic Rocks.Texture of Blueschist is Foliated whereas that of Skarn is Earthy, Mud-rich, Rough. Blueschist appears Dull and Banded and Skarn appears Dull. The luster of Blueschist is dull while that of Skarn is waxy and dull. Blueschist is available in blue, bluish - grey, purple, shades of blue colors whereas Skarn is available in black, brown, green, grey, white colors. The commercial uses of Blueschist are cemetery markers, commemorative tablets, creating artwork, curling, tombstones and that of Skarn are creating artwork, gemstone, jewelry, metallurgical flux, source of magnesia (mgo).