Definition
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism
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
Discoverer
Unknown
Unknown
Etymology
From Old French esclate, from esclat (French éclat)
From Latin Argilla (clay) and -ite in English which became agrilla+ -ite = Argillite
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated
Clastic, Polished
Color
Black, Brown, Buff, Green, Light to Dark Grey, Purple, Red, Shades of Blue
Dark Grey to Black, Pink, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull
Rough and Dull
Interior Uses
Bathrooms, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing, Whetstones
Construction Industry
As Dimension Stone
Used for flooring, stair treads, borders and window sills.
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Blackboards, Commemorative Tablets, Laboratory bench tops, Standard material for the bed of Billiard table, Standard material for the beds of Pool and Snooker table, Tombstones, Used in aquariums, Writing Slates
Fire resistant, Used to manufracture paperweights and bookends
Types
Not Available
Not Available
Features
Easily splits into thin plates, Surfaces are often shiny, Very fine grained rock
Is one of the oldest rock
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Formation
Slate is a low grade metamorphic rock that is generally formed by metamorphosis of mudstone or shale, under relatively low pressure and temperature conditions.
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.
Mineral Content
Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Iron(III) Oxide, Potassium Oxide, MgO, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Chemical Erosion
Grain Size
Very fine-grained
Fine Grained
Fracture
Splintery
Conchoidal to Uneven
Streak
Light to dark brown
White to Grey
Porosity
Less Porous
Highly Porous
Luster
Dull
Waxy and Dull
Compressive Strength
Not Available
Specific Gravity
2.65-2.8
2.56-2.68
Transparency
Opaque
Opaque
Density
2.6-2.8 g/cm3
2.54-2.66 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
China, India, Turkey
Bangladesh, China, India, Russia
Africa
Not Yet Found
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
Belgium, France, Germany, Italy, Norway, Portugal, Spain, United Kingdom
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Others
Arctic
Not Yet Found
Deposits in Western Continents
South America
Brazil
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
Not Yet Found
New South Wales, New Zealand, Queensland, Victoria, Western Australia
Slate vs Argillite 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. Slate vs Argillite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Slate and Properties of Argillite. Learn more about Slate vs Argillite in the next section. The interior uses of Slate include Bathrooms, Decorative aggregates, Entryways, Floor tiles, Flooring, Homes, Hotels, Interior decoration, Kitchens and Stair treads whereas the interior uses of Argillite include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Slate and Argillite, they have various applications in construction industry. The uses of Slate in construction industry include As dimension stone and that of Argillite include Used for flooring, stair treads, borders and window sills..
More about Slate and Argillite
Here you can know more about Slate and Argillite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Slate and Argillite consists of mineral content and compound content. The mineral content of Slate includes Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon and mineral content of Argillite includes Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz. You can also check out the list of all Metamorphic Rocks. When we have to compare Slate vs Argillite, the texture, color and appearance plays an important role in determining the type of rock. Slate is available in black, brown, buff, green, light to dark grey, purple, red, shades of blue colors whereas, Argillite is available in dark grey to black, pink, red, white colors. Appearance of Slate is Dull and that of Argillite is Rough and Dull. Properties of rock is another aspect for Slate vs Argillite. The hardness of Slate is 3-4 and that of Argillite is 2-3. The types of Slate are Not Available whereas types of Argillite are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Slate is light to dark brown while that of Argillite is white to grey. The specific heat capacity of Slate is 0.76 kJ/Kg K and that of Argillite is 0.87 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Slate is heat resistant, impact resistant, pressure resistant, wear resistant whereas Argillite is heat resistant, impact resistant.
