Definition
Argillites are highly compact sedimentary or slightly metamorphosed rocks that consist largely or wholly of particles of clay or silt but lack the fissility of shale or the cleavage characteristic of slate
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
Discoverer
Unknown
Unknown
Etymology
From Latin Argilla (clay) and -ite in English which became agrilla+ -ite = Argillite
From German Grauwacke, from grau grey + wacke
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic, Polished
Clastic
Color
Dark Grey to Black, Pink, Red, White
Beige, Black, Brown, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Rough and Dull
Dull
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Floor Tiles, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing, Whetstones
Curbing, Whetstones
Construction Industry
Used for flooring, stair treads, borders and window sills.
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Sculpture, Small Figurines
Commercial Uses
Fire resistant, Used to manufracture paperweights and bookends
As armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
Types
Metamorphic rock
Greywacke
Features
Is one of the oldest rock
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Archaeological Significance
Formation
An argillite is a fine-grained sedimentary rock mainly composed of clay particles which forms from lithified muds which contain variable amounts of silt-sized particles.
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.
Mineral Content
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Iron(III) Oxide, Potassium Oxide, MgO, Silicon Dioxide
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
Types of Metamorphism
-
-
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion
Coastal Erosion, Sea Erosion, Wind Erosion
Grain Size
Fine Grained
Angular and Fine
Fracture
Conchoidal to Uneven
Conchoidal
Streak
White to Grey
White
Porosity
Highly Porous
Highly Porous
Luster
Waxy and Dull
Dull
Specific Gravity
2.56-2.68
2.2-2.8
Transparency
Opaque
Opaque
Density
2.54-2.66 g/cm3
2.6-2.61 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Bangladesh, China, India, Russia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Namibia, Nigeria, South Africa
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Deposits in Western Continents
North America
USA
Canada, USA
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
New South Wales, New Zealand
All about Argillite and Greywacke Properties
Know all about Argillite and Greywacke properties here. All properties of rocks are important as they define the type of rock and its application. Argillite and Greywacke belong to Sedimentary Rocks.Texture of Argillite is Clastic, Polished whereas that of Greywacke is Clastic. Argillite appears Rough and Dull and Greywacke appears Dull. The luster of Argillite is waxy and dull while that of Greywacke is dull. Argillite is available in dark grey to black, pink, red, white colors whereas Greywacke is available in beige, black, brown, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors. The commercial uses of Argillite are fire resistant, used to manufracture paperweights and bookends and that of Greywacke are as armour rock for sea walls, petroleum reservoirs, sea defence, tombstones.