Definition
Schist is a medium grade metamorphic rock with medium to large, flat, sheet like grains in a preferred orientation
Variolites are a group of dark green basic igneous rocks which exhibit pale colored spots, or spherules, especially on weathered surfaces, that give them a pockmarked appearance
Discoverer
Unknown
Unknown
Etymology
From French schiste, Greek skhistos i.e. split
From Latin varius, speckled, variegated
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Group
Not Applicable
Volcanic
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Opaque Rock
Texture
Foliated, Platy
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Color
Black, Blue, Brown, Dark Brown, Green, Grey, Silver
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Appearance
Layered and Shiny
Dull and Soft
Interior Uses
Decorative Aggregates, Floor Tiles, Interior Decoration
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Exterior Uses
Garden Decoration, Paving Stone
Garden Decoration, Office Buildings
Other Architectural Uses
Not Yet Used
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, for Road Aggregate, Roadstone
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Used in aquariums, Writing Slates
Cemetery Markers, Creating Artwork
Types
Mica Schists, Calc-Silicate Schists, Graphite Schists, Blueschists, Whiteschists, Greenschists, Hornblende Schist, Talc Schist, Chlorite Schist, Garnet Schist, Glaucophane schist.
Not Available
Features
Easily splits into thin plates, Smooth to touch
Has High structural resistance against erosion and climate, Very fine grained rock
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Figurines
Not Yet Used
Used
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.
Variolites are a group of dark green basic igneous rocks that exhibit pale colored spots on weathered surfaces that give them a pockmarked appearance.
Mineral Content
Alusite, Amphibole, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc
Olivine, Plagioclase, Pyroxene
Compound Content
CaO, Carbon Dioxide, MgO
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional 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
Not Applicable
Grain Size
Medium to Fine Coarse Grained
Not Applicable
Fracture
Conchoidal
Conchoidal
Streak
White
White to Grey
Porosity
Highly Porous
Less Porous
Luster
Shiny
Not Available
Compressive Strength
Not Available
Cleavage
Slaty
Not Available
Specific Gravity
2.5-2.9
2.8-3
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
2.9-3.1 g/cm3
Specific Heat Capacity
Not Available
Resistance
Impact Resistant, Pressure Resistant, Water Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
India, Russia
Africa
Egypt, Ethiopia, Morocco, Nigeria, South Africa
South Africa
Europe
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Iceland
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
Canada, Costa Rica, Cuba, Mexico, Panama, USA
Canada, USA
South America
Brazil, Colombia, Guyana
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland
Not Yet Found
Schist vs Variolite 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 Variolite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Schist and Properties of Variolite. Learn more about Schist vs Variolite in the next section. The interior uses of Schist include Decorative aggregates, Floor tiles and Interior decoration whereas the interior uses of Variolite include Floor tiles, Flooring, Homes, Hotels and Kitchens. Due to some exceptional properties of Schist and Variolite, 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 Variolite include As dimension stone, Cobblestones, Rail track ballast, Roadstone.
More about Schist and Variolite
Here you can know more about Schist and Variolite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Schist and Variolite 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 Variolite includes Olivine, Plagioclase, Pyroxene. You can also check out the list of all Metamorphic Rocks. When we have to compare Schist vs Variolite, 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, Variolite is available in black, brown, light to dark grey colors. Appearance of Schist is Layered and Shiny and that of Variolite is Dull and Soft. Properties of rock is another aspect for Schist vs Variolite. The hardness of Schist is 3.5-4 and that of Variolite is 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 Variolite are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Schist is white while that of Variolite is white to grey. The specific heat capacity of Schist is Not Available and that of Variolite 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 Variolite is heat resistant, pressure resistant, wear resistant.