Definition
Eclogite is an extreme metamorphic rock, formed by regional metamorphism of basalt rock under very high pressure and temperature
  
Adakite is an intermediate to felsic volcanic rock that has geochemical characteristics of magma which is said to be formed by partial melting of altered basalt that is subducted below volcanic arcs
  
History
  
  
Origin
Unknown
  
Adak, Aleutian Islands
  
Discoverer
René Just Haüy
  
Defant and Drummond
  
Etymology
From French, Greek eklogē selection with reference to the selective content of the rock + -ite1
  
From Adak, Aleutian Islands
  
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, Opaque Rock
  
Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Texture
Earthy
  
Porphyritic
  
Color
Black, Brown, Colourless, Green, Grey, Pink, White
  
Black, Brown, Light to Dark Grey
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
No
  
No
  
Scratch Resistant
Yes
  
No
  
Stain Resistant
Yes
  
No
  
Wind Resistant
Yes
  
Yes
  
Acid Resistant
No
  
Yes
  
Appearance
Dull, Banded and Foilated
  
Dull and Soft
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Interior Decoration
  
Decorative Aggregates, Floor Tiles, Homes, Hotels, Kitchens
  
Exterior Uses
Paving Stone, Garden Decoration
  
As Building Stone, As Facing Stone, Office Buildings
  
Other Architectural Uses
Curbing
  
Whetstones
  
Industry
  
  
Construction Industry
Not Yet Used
  
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
  
Medical Industry
In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
  
Not Yet Used
  
Antiquity Uses
Artifacts
  
Monuments, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Gemstone
  
Commemorative Tablets, Pottery, Used in aquariums
  
Types
Not Available
  
Not Available
  
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Is one of the oldest rock
  
Has High structural resistance against erosion and climate, Host rock for Diamond, 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
  
Pictographs
Used
  
Used
  
Petroglyphs
Used
  
Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Absent
  
Absent
  
Formation
Eclogite forms from high-pressure metamorphism of mafic igneous rocks mainly, basalt or gabbro as it plunges into the mantle in a subduction zone.
  
Adakite rocks are formed when the hydrous fluids are released from minerals that break down in metamorphosed basalt, and rise into the mantle they initiate partial melting.
  
Composition
  
  
Mineral Content
Amphibole, Coesite, Corundum, Dolomite, Garnet, Kyanite, Lawsonite, Paragonite, Phengite, Pyroxene, Quartz, Rutile, Zoisite
  
Olivine, Plagioclase, Pyroxene
  
Compound Content
Aluminium Oxide, NaCl, CaO, Carbon Dioxide, Iron(III) Oxide, Magnesium Carbonate, MgO, Sodium Oxide, Potassium, Sodium
  
Aluminium Oxide, MgO, Silicon Dioxide
  
Transformation
  
  
Metamorphism
No
  
Yes
  
Types of Metamorphism
Not Applicable
  
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Weathering
Yes
  
Yes
  
Types of Weathering
Mechanical Weathering
  
Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Sea Erosion
  
Coastal Erosion, Sea Erosion, Water Erosion
  
Physical Properties
  
  
Hardness
3.5-4
  
3-4
  
Grain Size
Fine Grained
  
Fine to Medium Grained
  
Fracture
Not Available
  
Conchoidal
  
Streak
White
  
Bluish Black
  
Porosity
Less Porous
  
Less Porous
  
Luster
Subvitreous to Dull
  
Grainy, Pearly and Vitreous
  
Cleavage
Perfect
  
Not Available
  
Toughness
Not Available
  
Not Available
  
Specific Gravity
2.86-2.87
  
Not Available
  
Transparency
Opaque
  
Opaque
  
Density
3.2-3.6 g/cm3
  
Not Available
  
Thermal Properties
  
  
Resistance
Heat Resistant
  
Heat Resistant, Pressure Resistant, Wear Resistant
  
Deposits in Eastern Continents
  
  
Asia
India, Kazakhstan, Kuwait, Russia, South Korea, Thailand, Turkey
  
India, Russia
  
Africa
Ethiopia, Morocco, South Africa
  
Ethiopia, Somalia, South Africa
  
Europe
France, Germany, Italy, Norway, Scotland
  
Iceland
  
Others
Greenland
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, Costa Rica, Panama, USA
  
Canada, USA
  
South America
Argentina, Brazil, Colombia, Ecuador
  
Brazil
  
Deposits in Oceania Continent
  
  
Australia
Central Australia, New Zealand, Queensland
  
Not Yet Found