Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Eclogite is an extreme metamorphic rock, formed by regional metamorphism of basalt rock under very high pressure and temperature
Discoverer
Unknown
René Just Haüy
Etymology
From German Grauwacke, from grau grey + wacke
From French, Greek eklogē selection with reference to the selective content of the rock + -ite1
Class
Sedimentary Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Color
Beige, Black, Brown, Colourless, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Black, Brown, Colourless, Green, Grey, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull
Dull, Banded and Foilated
Interior Uses
Decorative Aggregates, Floor Tiles, Flooring, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Paving Stone, Garden Decoration
Other Architectural Uses
Curbing, Whetstones
Curbing
Construction Industry
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
Not Yet Used
Medical Industry
Not Yet Used
In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts
Commercial Uses
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
Creating Artwork, Gemstone
Types
Not Available
Not Available
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Available in Lots of Colors and Patterns, Generally rough to touch, Is one of the oldest rock
Archaeological Significance
Monuments
Not Yet Used
Not Yet Used
Famous Monuments
Not Applicable
Not Applicable
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Figurines
Used
Not Yet Used
Formation
Graywacke rock is a type of sedimentary rock, which is also known as immature sandstone, which is indurated, dark grey and consisting of poorly sorted angular to sub-angular, sand-sized grains.
Eclogite forms from high-pressure metamorphism of mafic igneous rocks mainly, basalt or gabbro as it plunges into the mantle in a subduction zone.
Mineral Content
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Amphibole, Coesite, Corundum, Dolomite, Garnet, Kyanite, Lawsonite, Paragonite, Phengite, Pyroxene, Quartz, Rutile, Zoisite
Compound Content
Aluminium Oxide, NaCl, CaO, Chromium(III) Oxide, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, NaCl, CaO, Carbon Dioxide, Iron(III) Oxide, Magnesium Carbonate, MgO, Sodium Oxide, Potassium, Sodium
Types of Metamorphism
Not Applicable
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering
Mechanical Weathering
Types of Erosion
Coastal Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Sea Erosion
Grain Size
Angular and Fine
Fine Grained
Fracture
Conchoidal
Not Available
Porosity
Highly Porous
Less Porous
Luster
Dull
Subvitreous to Dull
Toughness
2.6
Not Available
Specific Gravity
2.2-2.8
2.86-2.87
Transparency
Opaque
Opaque
Density
2.6-2.61 g/cm3
3.2-3.6 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
India, Kazakhstan, Kuwait, Russia, South Korea, Thailand, Turkey
Africa
Namibia, Nigeria, South Africa
Ethiopia, Morocco, South Africa
Europe
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
France, Germany, Italy, Norway, Scotland
Others
Greenland
Greenland
Deposits in Western Continents
North America
Canada, USA
Canada, Costa Rica, Panama, USA
South America
Brazil
Argentina, Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New South Wales, New Zealand
Central Australia, New Zealand, Queensland