Definition
Websterite is ultramafic and ultrabasic rock that consists of roughly equal proportions of orthopyroxene and clinopyroxene. It is a special type of pyroxenite.
Schist is a medium grade metamorphic rock with medium to large, flat, sheet like grains in a preferred orientation
Origin
Webster, North Carolina
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Discoverer
Unknown
Unknown
Etymology
From the town of Webster located in North Carolina
From French schiste, Greek skhistos i.e. split
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Clastic, Granular, Phaneritic, Porphyritic
Foliated, Platy
Color
Black to Grey, Bluish - Grey, Dark Greenish - Grey, Green, Light Greenish Grey
Black, Blue, Brown, Dark Brown, Green, Grey, Silver
Durability
Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Layered and Shiny
Interior Uses
Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Interior Decoration
Decorative Aggregates, Floor Tiles, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
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Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
As Dimension Stone, Building houses or walls, Cement Manufacture, for Road Aggregate, Roadstone
Antiquity Uses
Artifacts
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Used in aquariums, Writing Slates
Types
Ultramafic rock
Mica Schists, Calc-Silicate Schists, Graphite Schists, Blueschists, Whiteschists, Greenschists, Hornblende Schist, Talc Schist, Chlorite Schist, Garnet Schist, Glaucophane schist.
Features
Generally rough to touch, Is one of the oldest rock
Easily splits into thin plates, Smooth to touch
Archaeological Significance
Formation
Websterite can be formed as cumulates in ultramafic intrusions by accumulation of pyroxene crystals at the base of the lava chamber.
Schist formed by dynamic metamorphism at high temperatures and pressures that aligns the grains of mica, hornblende and other elongated minerals into thin layers.
Mineral Content
Amphibole, Augite, Bronzite, Chromite, Diopside, Enstatite, Garnet, Hornblende, Hypersthene, Magnetite, Pyroxene
Alusite, Amphibole, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc
Compound Content
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
CaO, Carbon Dioxide, MgO
Types of Metamorphism
Burial Metamorphism, Impact Metamorphism
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Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Coarse Grained
Medium to Fine Coarse Grained
Fracture
Uneven
Conchoidal
Streak
White, Greenish White or Grey
White
Porosity
Less Porous
Highly Porous
Luster
Dull to Vitreous to Submetallic
Shiny
Specific Gravity
3.2-3.5
2.5-2.9
Transparency
Opaque
Opaque
Density
3.1-3.6 g/cm3
2.8-2.9 g/cm3
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
Impact Resistant, Pressure Resistant, Water Resistant
Deposits in Eastern Continents
Asia
India, Russia
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
Africa
South Africa
Egypt, Ethiopia, Morocco, Nigeria, South Africa
Europe
Germany, Greece, Italy, Scotland, Turkey
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Deposits in Western Continents
North America
Canada, USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
Brazil, Colombia, Venezuela
Brazil, Colombia, Guyana
Deposits in Oceania Continent
Australia
New Zealand, Queensland
New South Wales, New Zealand, Queensland
All about Websterite and Schist Properties
Know all about Websterite and Schist properties here. All properties of rocks are important as they define the type of rock and its application. Websterite belongs to Igneous Rocks while Schist belongs to Metamorphic Rocks.Texture of Websterite is Clastic, Granular, Phaneritic, Porphyritic whereas that of Schist is Foliated, Platy. Websterite appears Layered, Banded, Veined and Shiny and Schist appears Layered and Shiny. The luster of Websterite is dull to vitreous to submetallic while that of Schist is shiny. Websterite is available in black to grey, bluish - grey, dark greenish - grey, green, light greenish grey colors whereas Schist is available in black, blue, brown, dark brown, green, grey, silver colors. The commercial uses of Websterite are cemetery markers, commemorative tablets, creating artwork, laboratory bench tops, jewelry, sea defence, tombstones and that of Schist are used in aquariums, writing slates.