Definition
Blueschist is a metamorphic rock which is generally blue in color and is formed under conditions of high pressure and low temperature
Gossan is intensely oxidized, weathered or decomposed rock, usually the upper and exposed part of an ore deposit or mineral vein.
Discoverer
Edgar Bailey
Cornish Gossen
Etymology
From French schiste, Greek skhistos i.e. split
From Cornish gossen from gos, blood from Old Cornish guit
Class
Metamorphic Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Foliated
Rough, Sandy
Color
Blue, Bluish - Grey, Purple, Shades of Blue
Brown, Brown- Black, Gold, Green, Rust
Durability
Durable
Durable
Appearance
Dull and Banded
Dull and Banded
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
-
Curbing
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
As Dimension Stone, 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, Gemstone
Types
Metamorphic rock
Translocated gossan and Leakage gossan
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Clasts are smooth to touch, Easily splits into thin plates
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.
Earth movements can cause rocks to be either deeply buried or squeezed and hence the rocks are heated and put under great pressure.
Mineral Content
Albite, Chlorite, Epidote, Garnet, Glaucophane, Lawsonite, Muscovite or Illite, Quartz
Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Fe, FeO, Silicon Dioxide, Sulphur
Types of Metamorphism
-
-
Types of Weathering
Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Grain Size
Fine to Medium Grained
Fine to Medium Grained
Fracture
Conchoidal
Conchoidal
Streak
White to Grey
White to Grey
Porosity
Highly Porous
Highly Porous
Specific Gravity
3-3.2
2.0
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
-9999 g/cm3
Resistance
Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Japan, Turkey
China, India, Indonesia, Russia, Singapore, South Korea
Africa
Egypt, Ethiopia, South Africa
Cape Verde, Ethiopia, Ghana, South Africa, Western Africa
Europe
France, Greece, Iceland
Albania, France, Germany, Great Britain, United Kingdom
Deposits in Western Continents
North America
USA
Canada, USA
South America
-
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New Zealand
New South Wales, South Australia, Western Australia
Blueschist vs Gossan 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. Blueschist vs Gossan characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Blueschist and Properties of Gossan. Learn more about Blueschist vs Gossan in the next section. The interior uses of Blueschist include Floor tiles, Flooring, Homes, Hotels and Kitchens whereas the interior uses of Gossan include Countertops, Decorative aggregates and Interior decoration. Due to some exceptional properties of Blueschist and Gossan, they have various applications in construction industry. The uses of Blueschist in construction industry include As dimension stone, Cobblestones, Rail track ballast, Roadstone and that of Gossan include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate.
More about Blueschist and Gossan
Here you can know more about Blueschist and Gossan. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Blueschist and Gossan consists of mineral content and compound content. The mineral content of Blueschist includes Albite, Chlorite, Epidote, Garnet, Glaucophane, Lawsonite, Muscovite or Illite, Quartz and mineral content of Gossan includes Apatite, Augite, Biotite, Bronzite, Calcite, Chert, Epidote, Feldspar, Hornblende, Micas, Plagioclase, Pyroxene, Quartz, Sulfides, Zircon. You can also check out the list of all Igneous Rocks. When we have to compare Blueschist vs Gossan, the texture, color and appearance plays an important role in determining the type of rock. Blueschist is available in blue, bluish - grey, purple, shades of blue colors whereas, Gossan is available in brown, brown- black, gold, green, rust colors. Appearance of Blueschist is Dull and Banded and that of Gossan is Dull and Banded. Properties of rock is another aspect for Blueschist vs Gossan. The hardness of Blueschist is 3.5-4 and that of Gossan is 4-5. The types of Blueschist are Metamorphic rock whereas types of Gossan are Translocated gossan and Leakage gossan. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Blueschist and Gossan is white to grey. The specific heat capacity of Blueschist is 0.84 kJ/Kg K and that of Gossan is 0.24 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Blueschist is impact resistant, pressure resistant whereas Gossan is heat resistant, impact resistant, pressure resistant.