Definition
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption
Discoverer
Unknown
Unknown
Etymology
From German Grauwacke, from grau grey + wacke
From a Latin word tophous then in Italian tufo and finally tuff
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
Clastic, Pyroclastic
Color
Beige, Black, Brown, Colourless, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Brown, Grey, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull
Dull, Vesicular and Foilated
Interior Uses
Decorative Aggregates, Floor Tiles, Flooring, Homes, Interior Decoration
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, 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
Building houses or walls, Construction Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
Creating Artwork
Types
Not Available
Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff, Andesitic tuff and Ignimbrite.
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Always found as volcanic pipes over deep continental crust
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Easter Island in the Polynesian Triangle, Pacific Ocean
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.
Tuff is formed when large masses of ash and sand which are mixed with hot gases are ejected by a volcano and avalanche rapidly down its slopes.
Mineral Content
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Calcite, Chlorite
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
Hydrogen Sulfide, Sulfur Dioxide
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional 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, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Angular and Fine
Fine Grained
Fracture
Conchoidal
Uneven
Porosity
Highly Porous
Highly Porous
Luster
Dull
Vitreous to Dull
Compressive Strength
Not Available
Cleavage
Perfect
Not Available
Toughness
2.6
Not Available
Specific Gravity
2.2-2.8
2.73
Transparency
Opaque
Opaque
Density
2.6-2.61 g/cm3
1-1.8 g/cm3
Specific Heat Capacity
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, Armenia, Azerbaijan, Burma, Cambodia, China, India, Indonesia, Iran, Japan, Malaysia, Mongolia, Nepal, North Korea, Pakistan, Saudi Arabia, Syria, Taiwan, Thailand, Turkey, Vietnam, Yemen
Africa
Namibia, Nigeria, South Africa
Cameroon, Cape Verde, Eritrea, Ethiopia, Kenya, Libya, Madagascar, Nigeria, Rwanda, South Africa, Sudan, Uganda
Europe
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
France, Georgia, Germany, Greece, Iceland, Italy, Netherlands, Poland, Portugal, Spain, United Kingdom
Others
Greenland
Antarctica, Hawaii Islands
Deposits in Western Continents
North America
Canada, USA
Canada, Costa Rica, Panama, USA
South America
Brazil
Argentina, Bolivia, Brazil, Chile, Ecuador, Paraguay
Deposits in Oceania Continent
Australia
New South Wales, New Zealand
Central Australia, Western Australia
Greywacke vs Tuff Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Greywacke vs Tuff characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Greywacke and Properties of Tuff. Learn more about Greywacke vs Tuff in the next section. The interior uses of Greywacke include Decorative aggregates, Floor tiles, Flooring, Homes and Interior decoration whereas the interior uses of Tuff include Decorative aggregates, Entryways, Flooring, Homes and Interior decoration. Due to some exceptional properties of Greywacke and Tuff, they have various applications in construction industry. The uses of Greywacke in construction industry include Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate, Raw material for the manufacture of mortar and that of Tuff include Building houses or walls, Construction aggregate.
More about Greywacke and Tuff
Here you can know more about Greywacke and Tuff. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Greywacke and Tuff consists of mineral content and compound content. The mineral content of Greywacke includes Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz and mineral content of Tuff includes Calcite, Chlorite. You can also check out the list of all Sedimentary Rocks. When we have to compare Greywacke vs Tuff, the texture, color and appearance plays an important role in determining the type of rock. 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, Tuff is available in brown, grey, yellow colors. Appearance of Greywacke is Dull and that of Tuff is Dull, Vesicular and Foilated. Properties of rock is another aspect for Greywacke vs Tuff. The hardness of Greywacke is 6-7 and that of Tuff is 4-6. The types of Greywacke are Not Available whereas types of Tuff are Welded tuff, Rhyolitic tuff, Basaltic tuff, Trachyte tuff, Andesitic tuff and Ignimbrite.. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Greywacke and Tuff is white. The specific heat capacity of Greywacke is Not Available and that of Tuff is 0.20 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Greywacke is heat resistant, impact resistant, pressure resistant whereas Tuff is heat resistant, impact resistant, pressure resistant, wear resistant.