Definition
Blueschist is a metamorphic rock which is generally blue in color and is formed under conditions of high pressure and low temperature
  
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption
  
History
  
  
Origin
USA
  
Italy
  
Discoverer
Edgar Bailey
  
Unknown
  
Etymology
From French schiste, Greek skhistos i.e. split
  
From a Latin word tophous then in Italian tufo and finally tuff
  
Class
Metamorphic Rocks
  
Igneous Rocks
  
Sub-Class
Durable Rock, Medium Hardness Rock
  
Durable Rock, Medium Hardness Rock
  
Family
  
  
Group
Not Applicable
  
Volcanic
  
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Foliated
  
Clastic, Pyroclastic
  
Color
Blue, Bluish - Grey, Purple, Shades of Blue
  
Brown, Grey, Yellow
  
Maintenance
Less
  
More
  
Durability
Durable
  
Durable
  
Water Resistant
No
  
Yes
  
Scratch Resistant
No
  
Yes
  
Stain Resistant
No
  
No
  
Wind Resistant
No
  
No
  
Acid Resistant
No
  
No
  
Appearance
Dull and Banded
  
Dull, Vesicular and Foilated
  
Architecture
  
  
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
  
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
  
Exterior Uses
Garden Decoration, Office Buildings
  
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
  
Other Architectural Uses
Not Yet Used
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
  
Building houses or walls, Construction Aggregate
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments, Sculpture
  
Artifacts, Monuments, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Tombstones
  
Creating Artwork
  
Types
Not Available
  
Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff, Andesitic tuff and Ignimbrite.
  
Features
Has High structural resistance against erosion and climate, Very fine grained rock
  
Always found as volcanic pipes over deep continental crust
  
Archaeological Significance
  
  
Monuments
Used
  
Used
  
Famous Monuments
Data Not Available
  
Easter Island in the Polynesian Triangle, Pacific Ocean
  
Sculpture
Used
  
Used
  
Famous Sculptures
Data Not Available
  
Data Not Available
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Used
  
Used
  
Fossils
Absent
  
Absent
  
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.
  
Tuff is formed when large masses of ash and sand which are mixed with hot gases are ejected by a volcano and avalanche rapidly down its slopes.
  
Composition
  
  
Mineral Content
Albite, Chlorite, Epidote, Garnet, Glaucophane, Lawsonite, Muscovite or Illite, Quartz
  
Calcite, Chlorite
  
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
  
Hydrogen Sulfide, Sulfur Dioxide
  
Transformation
  
  
Metamorphism
No
  
Yes
  
Types of Metamorphism
Not Applicable
  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Weathering
Yes
  
Yes
  
Types of Weathering
Mechanical Weathering
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
  
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
3.5-4
  
4-6
  
Grain Size
Fine to Medium Grained
  
Fine Grained
  
Fracture
Conchoidal
  
Uneven
  
Streak
White to Grey
  
White
  
Porosity
Highly Porous
  
Highly Porous
  
Luster
Dull
  
Vitreous to Dull
  
Compressive Strength
Not Available
  
243.80 N/mm
2
  
5
Cleavage
Slaty
  
Not Available
  
Toughness
1.5
  
Not Available
  
Specific Gravity
3-3.2
  
2.73
  
Transparency
Opaque
  
Opaque
  
Density
2.8-2.9 g/cm3
  
1-1.8 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
Not Available
  
0.20 kJ/Kg K
  
25
Resistance
Impact Resistant, Pressure Resistant
  
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
  
Deposits in Eastern Continents
  
  
Asia
Japan, Turkey
  
Afghanistan, Armenia, Azerbaijan, Burma, Cambodia, China, India, Indonesia, Iran, Japan, Malaysia, Mongolia, Nepal, North Korea, Pakistan, Saudi Arabia, Syria, Taiwan, Thailand, Turkey, Vietnam, Yemen
  
Africa
Egypt, Ethiopia, South Africa
  
Cameroon, Cape Verde, Eritrea, Ethiopia, Kenya, Libya, Madagascar, Nigeria, Rwanda, South Africa, Sudan, Uganda
  
Europe
France, Greece, Iceland
  
France, Georgia, Germany, Greece, Iceland, Italy, Netherlands, Poland, Portugal, Spain, United Kingdom
  
Others
Not Yet Found
  
Antarctica, Hawaii Islands
  
Deposits in Western Continents
  
  
North America
USA
  
Canada, Costa Rica, Panama, USA
  
South America
Not Yet Found
  
Argentina, Bolivia, Brazil, Chile, Ecuador, Paraguay
  
Deposits in Oceania Continent
  
  
Australia
New Zealand
  
Central Australia, Western Australia
  
Blueschist vs Tuff 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 Tuff characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Blueschist and Properties of Tuff. Learn more about Blueschist vs Tuff in the next section. The interior uses of Blueschist include Floor tiles, Flooring, Homes, Hotels and Kitchens whereas the interior uses of Tuff include Decorative aggregates, Entryways, Flooring, Homes and Interior decoration. Due to some exceptional properties of Blueschist and Tuff, 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 Tuff include Building houses or walls, Construction aggregate.
More about Blueschist and Tuff
Here you can know more about Blueschist and Tuff. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Blueschist and Tuff 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 Tuff includes Calcite, Chlorite. You can also check out the list of all Igneous Rocks. When we have to compare Blueschist vs Tuff, 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, Tuff is available in brown, grey, yellow colors. Appearance of Blueschist is Dull and Banded and that of Tuff is Dull, Vesicular and Foilated. Properties of rock is another aspect for Blueschist vs Tuff. The hardness of Blueschist is 3.5-4 and that of Tuff is 4-6. The types of Blueschist are Not Available whereas types of Tuff are Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff, Andesitic tuff and Ignimbrite.. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Blueschist is white to grey while that of Tuff is white. The specific heat capacity of Blueschist is Not Available and that of Tuff is 0.20 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 Tuff is heat resistant, impact resistant, pressure resistant, wear resistant.