Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Scoria is a dark-colored extrusive igneous rock with abundant round bubble-like cavities
Discoverer
Unknown
Unknown
Etymology
From German Grauwacke, from grau grey + wacke
From late Middle English (denoting slag from molten metal), from Greek skōria refuse, from skōr dung
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic
Vesicular
Color
Beige, Black, Brown, Colourless, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Black, Brown, Dark Grey to Black, Red
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull
Glassy and Vesicular
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
Garden Decoration, Paving Stone
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
Cement Manufacture, Construction Aggregate, for Road Aggregate, In landscaping and drainage works
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
As a traction material on snow-covered roads, Creating Artwork, High-temperature insulation, In gas barbecue grills
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, 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.
Scoria forms when magma containing huge amount of dissolved gas flows from a volcano during an eruption.
Mineral Content
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Apatite, Biotite, Calcite, Feldspar, Hematite, Hornblade, Ilmenite, Magnetite, Olivine, Pyroxene, Quartz, Silica
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
Ca, NaCl
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Sea Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Angular and Fine
Fine Grained
Fracture
Conchoidal
Conchoidal
Porosity
Highly Porous
Highly Porous
Luster
Dull
Subvitreous to Dull
Specific Gravity
2.2-2.8
Not Available
Transparency
Opaque
Opaque
Density
2.6-2.61 g/cm3
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Afghanistan, Indonesia, Japan, Russia
Africa
Namibia, Nigeria, South Africa
Ethiopia, Kenya, Tanzania
Europe
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Greece, Hungary, Iceland, Italy, Turkey
Others
Greenland
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA
South America
Brazil
Argentina, Chile, Ecuador, Peru
Deposits in Oceania Continent
Australia
New South Wales, New Zealand
New Zealand, Western Australia
All about Greywacke and Scoria Properties
Know all about Greywacke and Scoria properties here. All properties of rocks are important as they define the type of rock and its application. Greywacke belongs to Sedimentary Rocks while Scoria belongs to Igneous Rocks.Texture of Greywacke is Clastic whereas that of Scoria is Vesicular. Greywacke appears Dull and Scoria appears Glassy and Vesicular. The luster of Greywacke is dull while that of Scoria is subvitreous to dull. 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 Scoria is available in black, brown, dark grey to black, red colors. The commercial uses of Greywacke are as armour rock for sea walls, petroleum reservoirs, sea defence, tombstones and that of Scoria are as a traction material on snow-covered roads, creating artwork, high-temperature insulation, in gas barbecue grills.