Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Mylonite is a metamorphic rock formed by ductile deformation during intense shearing encountered during folding and faulting, a process termed cataclastic or dynamic metamorphism
Origin
Unknown
New Zealand
Discoverer
Unknown
Unknown
Etymology
From German Grauwacke, from grau grey + wacke
From Greek mulōn mill + -ite
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 to Grey
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
As Building Stone, As Facing 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
for Road Aggregate, Landscaping, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
Creating Artwork, Gemstone, Jewelry
Types
Not Available
Blastomylonites, Ultramylonites and Phyllonites
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Surfaces are often shiny
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Not Used
Used
Petroglyphs
Not Used
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.
Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones.
Mineral Content
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Porphyroblasts
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, Calcium Sulfate, Chromium(III) Oxide, Iron(III) Oxide, Magnesium Carbonate, Silicon Dioxide
Types of Metamorphism
Not Applicable
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Wind Erosion
Grain Size
Angular and Fine
Fine Grained
Fracture
Conchoidal
Conchoidal
Porosity
Highly Porous
Highly Porous
Compressive Strength
Not Available
Cleavage
Perfect
Conchoidal
Toughness
2.6
Not Available
Specific Gravity
2.2-2.8
2.97-3.05
Transparency
Opaque
Opaque
Density
2.6-2.61 g/cm3
2.6-4.8 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
China, India, Indonesia, Saudi Arabia, South Korea
Africa
Namibia, Nigeria, South Africa
Eritrea, Ethiopia, Ghana, South Africa, Western Africa
Europe
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
England, Finland, France, Germany, Great Britain, Greece, United Kingdom
Others
Greenland
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
USA
South America
Brazil
Not Yet Found
Deposits in Oceania Continent
Australia
New South Wales, New Zealand
Central Australia, Western Australia
All about Greywacke and Mylonite Properties
Know all about Greywacke and Mylonite properties here. All properties of rocks are important as they define the type of rock and its application. Greywacke belongs to Sedimentary Rocks while Mylonite belongs to Metamorphic Rocks.Texture of Greywacke is Clastic whereas that of Mylonite is Foliated. Greywacke appears Dull and Mylonite appears Dull, Banded and Foilated. The luster of Greywacke is dull while that of Mylonite is shiny. Greywacke is available in beige, black, brown, colourless, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors whereas Mylonite is available in black to grey colors. The commercial uses of Greywacke are as armour rock for sea walls, petroleum reservoirs, sea defence, tombstones and that of Mylonite are creating artwork, gemstone, jewelry.