Definition
Scoria is a dark-colored extrusive igneous rock with abundant round bubble-like cavities
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
Discoverer
Unknown
Tornebohm
Etymology
From late Middle English (denoting slag from molten metal), from Greek skōria refuse, from skōr dung
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Vesicular
Earthy, Mud-rich, Rough
Color
Black, Brown, Dark Grey to Black, Red
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Glassy and Vesicular
Dull
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, In landscaping and drainage works
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
As a traction material on snow-covered roads, Creating Artwork, High-temperature insulation, In gas barbecue grills
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Types
Basaltic Scoria and Andesitic Scoria
Endoskarns
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Surfaces are often shiny
Host Rock for Lead, Zinc and Copper Deposits
Archaeological Significance
Formation
Scoria forms when magma containing huge amount of dissolved gas flows from a volcano during an eruption.
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
Apatite, Biotite, Calcite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz, Silica
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Compound Content
Ca, NaCl
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
-
Grain Size
Fine Grained
Fine Grained
Fracture
Conchoidal
Irregular
Streak
White
Light to dark brown
Porosity
Highly Porous
Less Porous
Luster
Subvitreous to Dull
Waxy and Dull
Specific Gravity
-9999
2.86
Transparency
Opaque
Opaque
Density
-9999 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Africa
Ethiopia, Kenya, Tanzania
South Africa, Western Africa
Europe
Greece, Hungary, Iceland, Italy, Turkey
United Kingdom
Deposits in Western Continents
North America
Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA
Canada
South America
Argentina, Chile, Ecuador, Peru
Brazil, Colombia, Paraguay
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
Central Australia, Western Australia
Scoria vs Skarn 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. Scoria vs Skarn characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Scoria and Properties of Skarn. Learn more about Scoria vs Skarn in the next section. The interior uses of Scoria include Decorative aggregates and Interior decoration whereas the interior uses of Skarn include Decorative aggregates, Entryways and Interior decoration. Due to some exceptional properties of Scoria and Skarn, they have various applications in construction industry. The uses of Scoria in construction industry include Cement manufacture, Construction aggregate, For road aggregate, In landscaping and drainage works and that of Skarn 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.
More about Scoria and Skarn
Here you can know more about Scoria and Skarn. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Scoria and Skarn consists of mineral content and compound content. The mineral content of Scoria includes Apatite, Biotite, Calcite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz, Silica and mineral content of Skarn includes Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite. You can also check out the list of all Igneous Rocks. When we have to compare Scoria vs Skarn, the texture, color and appearance plays an important role in determining the type of rock. Scoria is available in black, brown, dark grey to black, red colors whereas, Skarn is available in black, brown, green, grey, white colors. Appearance of Scoria is Glassy and Vesicular and that of Skarn is Dull. Properties of rock is another aspect for Scoria vs Skarn. The hardness of Scoria is 5-6 and that of Skarn is 6.5. The types of Scoria are Basaltic Scoria and Andesitic Scoria whereas types of Skarn are Endoskarns. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Scoria is white while that of Skarn is light to dark brown. The specific heat capacity of Scoria is 0.84 kJ/Kg K and that of Skarn is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Scoria is heat resistant, impact resistant, pressure resistant, wear resistant whereas Skarn is heat resistant.