Definition
Schist is a medium grade metamorphic rock with medium to large, flat, sheet like grains in a preferred orientation
Scoria is a dark-colored extrusive igneous rock with abundant round bubble-like cavities
Discoverer
Unknown
Unknown
Etymology
From French schiste, Greek skhistos i.e. split
From late Middle English (denoting slag from molten metal), from Greek skōria refuse, from skōr dung
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated, Platy
Vesicular
Color
Black, Blue, Brown, Dark Brown, Green, Grey, Silver
Black, Brown, Dark Grey to Black, Red
Durability
Durable
Durable
Appearance
Layered and Shiny
Glassy and Vesicular
Interior Uses
Decorative Aggregates, Floor Tiles, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
Garden Decoration, Paving Stone
Garden Decoration, Paving Stone
Other Architectural Uses
-
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, for Road Aggregate, Roadstone
Cement Manufacture, Construction Aggregate, for Road Aggregate, In landscaping and drainage works
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Used in aquariums, Writing Slates
As a traction material on snow-covered roads, Creating Artwork, High-temperature insulation, In gas barbecue grills
Types
Mica Schists, Calc-Silicate Schists, Graphite Schists, Blueschists, Whiteschists, Greenschists, Hornblende Schist, Talc Schist, Chlorite Schist, Garnet Schist, Glaucophane schist.
Basaltic Scoria and Andesitic Scoria
Features
Easily splits into thin plates, Smooth to touch
Available in Lots of Colors and Patterns, Generally rough to touch, Surfaces are often shiny
Archaeological Significance
Formation
Schist formed by dynamic metamorphism at high temperatures and pressures that aligns the grains of mica, hornblende and other elongated minerals into thin layers.
Scoria forms when magma containing huge amount of dissolved gas flows from a volcano during an eruption.
Mineral Content
Alusite, Amphibole, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc
Apatite, Biotite, Calcite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz, Silica
Compound Content
CaO, Carbon Dioxide, MgO
Ca, NaCl
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Conchoidal
Conchoidal
Porosity
Highly Porous
Highly Porous
Luster
Shiny
Subvitreous to Dull
Specific Gravity
2.5-2.9
-9999
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
-9999 g/cm3
Resistance
Impact Resistant, Pressure Resistant, Water Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
Afghanistan, Indonesia, Japan, Russia
Africa
Egypt, Ethiopia, Morocco, Nigeria, South Africa
Ethiopia, Kenya, Tanzania
Europe
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Greece, Hungary, Iceland, Italy, Turkey
Deposits in Western Continents
North America
Canada, Costa Rica, Cuba, Mexico, Panama, USA
Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA
South America
Brazil, Colombia, Guyana
Argentina, Chile, Ecuador, Peru
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland
New Zealand, Western Australia
Schist vs Scoria 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. Schist vs Scoria characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Schist and Properties of Scoria. Learn more about Schist vs Scoria in the next section. The interior uses of Schist include Decorative aggregates, Floor tiles and Interior decoration whereas the interior uses of Scoria include Decorative aggregates and Interior decoration. Due to some exceptional properties of Schist and Scoria, they have various applications in construction industry. The uses of Schist in construction industry include As dimension stone, Building houses or walls, Cement manufacture, For road aggregate, Roadstone and that of Scoria include Cement manufacture, Construction aggregate, For road aggregate, In landscaping and drainage works.
More about Schist and Scoria
Here you can know more about Schist and Scoria. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Schist and Scoria consists of mineral content and compound content. The mineral content of Schist includes Alusite, Amphibole, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc and mineral content of Scoria includes Apatite, Biotite, Calcite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz, Silica. You can also check out the list of all Metamorphic Rocks. When we have to compare Schist vs Scoria, the texture, color and appearance plays an important role in determining the type of rock. Schist is available in black, blue, brown, dark brown, green, grey, silver colors whereas, Scoria is available in black, brown, dark grey to black, red colors. Appearance of Schist is Layered and Shiny and that of Scoria is Glassy and Vesicular. Properties of rock is another aspect for Schist vs Scoria. The hardness of Schist is 3.5-4 and that of Scoria is 5-6. The types of Schist are Mica Schists, Calc-Silicate Schists, Graphite Schists, Blueschists, Whiteschists, Greenschists, Hornblende Schist, Talc Schist, Chlorite Schist, Garnet Schist, Glaucophane schist. whereas types of Scoria are Basaltic Scoria and Andesitic Scoria. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Schist and Scoria is white. The specific heat capacity of Schist is 0.70 kJ/Kg K and that of Scoria is 0.84 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Schist is impact resistant, pressure resistant, water resistant whereas Scoria is heat resistant, impact resistant, pressure resistant, wear resistant.