Definition
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
History
Origin
-
Discoverer
Unknown
Etymology
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
Class
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Family
Group
-
Other Categories
Fine Grained Rock, Opaque Rock
Texture
Banded, Rough
Color
Black, Brown, Green, Grey, Red, White
Maintenance
Less
Durability
Durable
Water Resistant
✔
✘
58% - Sedimentary Rocks Rocks have it !
Scratch Resistant
✔
✘
61% - Sedimentary Rocks Rocks have it !
Stain Resistant
✔
✘
42% - Sedimentary Rocks Rocks have it !
Wind Resistant
✔
✘
36% - Sedimentary Rocks Rocks
Acid Resistant
✔
✘
19% - Sedimentary Rocks Rocks have it !
Appearance
Glassy or Pearly
Architecture
Interior Uses
Decorative Aggregates, Homes
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Industry
Construction Industry
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
Medical Industry
-
Antiquity Uses
Artifacts, Monuments
Other Uses
Commercial Uses
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
Types
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Features
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Archaeological Significance
Monuments
-
Famous Monuments
-
Sculpture
-
Famous Sculptures
-
Pictographs
-
Petroglyphs
-
Figurines
-
Fossils
Present
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.
Composition
Mineral Content
Quartz, Silicon
Compound Content
Silicon Dioxide
Transformation
Metamorphism
✔
✘
17% - Sedimentary Rocks Rocks
Types of Metamorphism
-
Weathering
✔
✘
78% - Sedimentary Rocks Rocks
Types of Weathering
-
Erosion
✔
✘
86% - Sedimentary Rocks Rocks have it !
Types of Erosion
Chemical Erosion
Physical Properties
Hardness
6.5-7
1
7
👆🏻
Grain Size
Very fine-grained
Fracture
Uneven, Splintery or Conchoidal
Streak
White
Porosity
Highly Porous
Luster
Waxy and Dull
Compressive Strength
450.00 N/mm2
Rank: 1 (Overall)
0.15
450
👆🏻
Cleavage
-
Toughness
1.5
Specific Gravity
2.5-2.8
0
8.4
👆🏻
Transparency
Translucent to Opaque
Density
2.7 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.74 kJ/Kg K
Rank: 21 (Overall)
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Kenya, Morocco, South Africa, Tanzania
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Others
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Canada, Mexico, USA
South America
Bolivia, Brazil
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia