Definition
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
  
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
  
History
  
  
Origin
Unknown
  
England
  
Discoverer
Unknown
  
Unknown
  
Etymology
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
  
From Old French esclate, from esclat (French éclat)
  
Class
Sedimentary Rocks
  
Metamorphic Rocks
  
Sub-Class
Durable Rock, Hard Rock
  
Durable Rock, Medium Hardness Rock
  
Family
  
  
Group
Not Applicable
  
Not Applicable
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Banded, Rough
  
Foliated
  
Color
Black, Brown, Green, Grey, Red, White
  
Black, Brown, Buff, Green, Light to Dark Grey, Purple, Red, Shades of Blue
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
Yes
  
Yes
  
Wind Resistant
No
  
No
  
Acid Resistant
Yes
  
No
  
Appearance
Glassy or Pearly
  
Dull
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Homes
  
Bathrooms, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
  
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
  
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
  
As Dimension Stone
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments
  
Artifacts, Monuments, Sculpture, Small Figurines
  
Other Uses
  
  
Commercial Uses
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
  
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
  
Types
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
  
Not Available
  
Features
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
  
Easily splits into thin plates, Surfaces are often shiny, Very fine grained rock
  
Archaeological Significance
  
  
Monuments
Used
  
Used
  
Famous Monuments
Data Not Available
  
Data Not Available
  
Sculpture
Not Yet Used
  
Used
  
Famous Sculptures
Not Applicable
  
Data Not Available
  
Pictographs
Not Used
  
Used
  
Petroglyphs
Not Used
  
Used
  
Figurines
Not Yet Used
  
Used
  
Fossils
Present
  
Absent
  
Formation
Chert forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The chert formation can be either of chemical or biological origin.
  
Slate is a low grade metamorphic rock that is generally formed by metamorphosis of mudstone or shale, under relatively low pressure and temperature conditions.
  
Composition
  
  
Mineral Content
Quartz, Silicon
  
Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon
  
Compound Content
Silicon Dioxide
  
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
  
Transformation
  
  
Metamorphism
No
  
Yes
  
Types of Metamorphism
Not Applicable
  
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
  
Weathering
No
  
Yes
  
Types of Weathering
Not Applicable
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion
  
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
  
Physical Properties
  
  
Hardness
6.5-7
  
3-4
  
Grain Size
Very fine-grained
  
Very fine-grained
  
Fracture
Uneven, Splintery or Conchoidal
  
Splintery
  
Streak
White
  
Light to dark brown
  
Porosity
Highly Porous
  
Less Porous
  
Luster
Waxy and Dull
  
Dull
  
Compressive Strength
450.00 N/mm2
  
1
30.00 N/mm2
  
30
Cleavage
Non-Existent
  
Slaty
  
Toughness
1.5
  
1.2
  
Specific Gravity
2.5-2.8
  
2.65-2.8
  
Transparency
Translucent to Opaque
  
Opaque
  
Density
2.7 g/cm3
  
2.6-2.8 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.74 kJ/Kg K
  
19
0.76 kJ/Kg K
  
17
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
  
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
  
Deposits in Eastern Continents
  
  
Asia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
  
China, India, Turkey
  
Africa
Kenya, Morocco, South Africa, Tanzania
  
Not Yet Found
  
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
  
Belgium, France, Germany, Italy, Norway, Portugal, Spain, United Kingdom
  
Others
Greenland, Mid-Atlantic Ridge
  
Arctic
  
Deposits in Western Continents
  
  
North America
Canada, Mexico, USA
  
USA
  
South America
Bolivia, Brazil
  
Brazil
  
Deposits in Oceania Continent
  
  
Australia
New South Wales, Queensland, South Australia, Western Australia
  
Not Yet Found
  
All about Chert and Slate Properties
Know all about Chert and Slate properties here. All properties of rocks are important as they define the type of rock and its application. Chert belongs to Sedimentary Rocks while Slate belongs to Metamorphic Rocks.Texture of Chert is Banded, Rough whereas that of Slate is Foliated. Chert appears Glassy or Pearly and Slate appears Dull. The luster of Chert is waxy and dull while that of Slate is dull. Chert is available in black, brown, green, grey, red, white colors whereas Slate is available in black, brown, buff, green, light to dark grey, purple, red, shades of blue colors. The commercial uses of Chert are creating artwork, gemstone, in fire-starting tools, jewelry, to ignite fire, used in flintlock firearms and that of Slate are 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.