Definition
Blueschist is a metamorphic rock which is generally blue in color and is formed under conditions of high pressure and low temperature
Websterite is ultramafic and ultrabasic rock that consists of roughly equal proportions of orthopyroxene and clinopyroxene. It is a special type of pyroxenite.
Origin
USA
Webster, North Carolina
Discoverer
Edgar Bailey
Unknown
Etymology
From French schiste, Greek skhistos i.e. split
From the town of Webster located in North Carolina
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Foliated
Clastic, Granular, Phaneritic, Porphyritic
Color
Blue, Bluish - Grey, Purple, Shades of Blue
Black to Grey, Bluish - Grey, Dark Greenish - Grey, Green, Light Greenish Grey
Durability
Durable
Durable
Appearance
Dull and Banded
Layered, Banded, Veined and Shiny
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, 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 Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Tombstones
Cemetery Markers, Commemorative Tablets, Creating Artwork, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Types
Metamorphic rock
Ultramafic rock
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Generally rough to touch, Is one of the oldest rock
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.
Websterite can be formed as cumulates in ultramafic intrusions by accumulation of pyroxene crystals at the base of the lava chamber.
Mineral Content
Albite, Chlorite, Epidote, Garnet, Glaucophane, Lawsonite, Muscovite or Illite, Quartz
Amphibole, Augite, Bronzite, Chromite, Diopside, Enstatite, Garnet, Hornblende, Hypersthene, Magnetite, Pyroxene
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Types of Metamorphism
-
Burial Metamorphism, Impact Metamorphism
Types of Weathering
Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Grain Size
Fine to Medium Grained
Coarse Grained
Fracture
Conchoidal
Uneven
Streak
White to Grey
White, Greenish White or Grey
Porosity
Highly Porous
Less Porous
Luster
Dull
Dull to Vitreous to Submetallic
Specific Gravity
3-3.2
3.2-3.5
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
3.1-3.6 g/cm3
Resistance
Impact Resistant, Pressure Resistant
Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Japan, Turkey
India, Russia
Africa
Egypt, Ethiopia, South Africa
South Africa
Europe
France, Greece, Iceland
Germany, Greece, Italy, Scotland, Turkey
Deposits in Western Continents
North America
USA
Canada, USA
South America
-
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New Zealand
New Zealand, Queensland
All about Blueschist and Websterite Properties
Know all about Blueschist and Websterite properties here. All properties of rocks are important as they define the type of rock and its application. Blueschist belongs to Metamorphic Rocks while Websterite belongs to Igneous Rocks.Texture of Blueschist is Foliated whereas that of Websterite is Clastic, Granular, Phaneritic, Porphyritic. Blueschist appears Dull and Banded and Websterite appears Layered, Banded, Veined and Shiny. The luster of Blueschist is dull while that of Websterite is dull to vitreous to submetallic. Blueschist is available in blue, bluish - grey, purple, shades of blue colors whereas Websterite is available in black to grey, bluish - grey, dark greenish - grey, green, light greenish grey colors. The commercial uses of Blueschist are cemetery markers, commemorative tablets, creating artwork, curling, tombstones and that of Websterite are cemetery markers, commemorative tablets, creating artwork, laboratory bench tops, jewelry, sea defence, tombstones.