Definition
Eclogite is an extreme metamorphic rock, formed by regional metamorphism of basalt rock under very high pressure and temperature
Tonalite is a coarse-grained plutonic rock consisting mainly of sodic plagioclase, quartz, and hornblende or other mafic minerals with phaneritic texture
History
Origin
-
Tonale, Italy
Discoverer
René Just Haüy
Warren Hamilton
Etymology
From French, Greek eklogē selection with reference to the selective content of the rock + -ite1
From Tonale Pass, northern Italy, + -ite1
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Family
Group
-
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Earthy
Phaneritic
Color
Black, Brown, Green, Grey, Pink, White
Black, Brown, Light to Dark Grey, White
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull, Banded and Foilated
Banded and Foilated
Architecture
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Exterior Uses
Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
-
As Dimension Stone, Cement Manufacture, Cobblestones, Construction Aggregate, for Road Aggregate
Medical Industry
In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
-
Antiquity Uses
Artifacts
Artifacts, Sculpture
Other Uses
Commercial Uses
Creating Artwork, Gemstone
Cemetery Markers, Creating Artwork
Types
Eclogite
Dacite
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Is one of the oldest rock
Is one of the oldest rock, Typically speckled black and white.
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
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.
When alkali feldspar is extracted from granite, it changes to granitoid and later, it becomes tonalite with quartz as major mineral.
Composition
Mineral Content
Amphibole, Coesite, Corundum, Dolomite, Garnet, Kyanite, Lawsonite, Paragonite, Phengite, Pyroxene, Quartz, Rutile, Zoisite
Albite, Amphibole, Apatite, Biotite, Feldspar, Hornblade, Ilmenite, Magnetite, Manganese Oxides, Olivine, Plagioclase, Pyroxene, Quartz, Sulfides, Titanite, Zircon
Compound Content
Aluminium Oxide, NaCl, CaO, Carbon Dioxide, Iron(III) Oxide, Magnesium Carbonate, MgO, Sodium Oxide, Potassium, Sodium
NaCl, CaO, MgO, Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Sea Erosion
Wind Erosion
Physical Properties
Hardness
3.5-46-7
1
7
👆🏻
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
-
Conchoidal
Streak
White
Bluish Black
Porosity
Less Porous
Very Less Porous
Luster
Subvitreous to Dull
Subvitreous to Dull
Compressive Strength
200.00 N/mm2185.00 N/mm2
0.15
450
👆🏻
Cleavage
Perfect
-
Toughness
-
2.1
Specific Gravity
2.86-2.872.86-3
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
3.2-3.6 g/cm32.73 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.75 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant
Heat Resistant, Pressure Resistant, Water Resistant
Deposits in Eastern Continents
Asia
India, Kazakhstan, Kuwait, Russia, South Korea, Thailand, Turkey
-
Africa
Ethiopia, Morocco, South Africa
Egypt
Europe
France, Germany, Italy, Norway, Scotland
Finland, Germany, Italy, Romania, Sweden, Turkey
Others
Greenland
-
Deposits in Western Continents
North America
Canada, Costa Rica, Panama, USA
USA
South America
Argentina, Brazil, Colombia, Ecuador
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru
Deposits in Oceania Continent
Australia
Central Australia, New Zealand, Queensland
New Zealand, South Australia, Western Australia