Definition
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Quartzite is a non-foliated metamorphic rock that forms by the metamorphism of pure quartz Sandstone
Discoverer
Unknown
Unknown
Etymology
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
From quartz + -ite
Class
Sedimentary Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Medium Grained Rock, Opaque Rock
Texture
Banded, Rough
Foliated, Granular
Color
Black, Brown, Green, Grey, Red, White
Black, Blue, Brown, Green, Light Grey, Purple, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Glassy or Pearly
Lustrous
Interior Uses
Decorative Aggregates, Homes
Countertops, Decorative Aggregates, Flooring, Homes
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
Construction Industry
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
Arrowheads, As Dimension Stone, Cement Manufacture, Construction Aggregate, Cutting Tool, for Road Aggregate, Making natural cement, Production of Glass and Ceramics, Rail Track Ballast, Roadstone
Antiquity Uses
Artifacts, Monuments
Artifacts, Jewellery, Monuments, Sculpture
Commercial Uses
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
An Oil and Gas Reservoir, As armour rock for sea walls, Cemetery Markers, Commemorative Tablets, In aquifers, Laboratory bench tops, Petroleum reservoirs, Soil Conditioner, Source of Magnesia (MgO), Tombstones, Used in aquariums
Types
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Orthoquartzite and Metaquartzite
Features
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Generally rough to touch, Is one of the oldest rock
Archaeological Significance
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.
Quartzite forms from sandstone and the mineral quartz being put under extreme heat and pressure.
Mineral Content
Quartz, Silicon
Chlorite, Epidote, Hematite, Kyanite, Magnetite, Muscovite or Illite, Quartz
Compound Content
Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, MgO, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Hydrothermal Metamorphism, Regional Metamorphism
Types of Weathering
-
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Medium Grained
Fracture
Uneven, Splintery or Conchoidal
Uneven, Splintery or Conchoidal
Porosity
Highly Porous
Less Porous
Luster
Waxy and Dull
Vitreous
Specific Gravity
2.5-2.8
2.6-2.8
Transparency
Translucent to Opaque
Transparent to Translucent
Density
2.7 g/cm3
2.32-2.42 g/cm3
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, Israel, Russia, South Korea, Thailand, Turkey
Africa
Kenya, Morocco, South Africa, Tanzania
Ethiopia, Morocco, South Africa, Zimbabwe
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
England, Italy, Norway, Scotland, Sweden, United Kingdom
Others
Greenland, Mid-Atlantic Ridge
Greenland
Deposits in Western Continents
North America
Canada, Mexico, USA
Bahamas, Canada, USA
South America
Bolivia, Brazil
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
New Zealand, Queensland, Western Australia
All about Chert and Quartzite Properties
Know all about Chert and Quartzite properties here. All properties of rocks are important as they define the type of rock and its application. Chert belongs to Sedimentary Rocks while Quartzite belongs to Metamorphic Rocks.Texture of Chert is Banded, Rough whereas that of Quartzite is Foliated, Granular. Chert appears Glassy or Pearly and Quartzite appears Lustrous. The luster of Chert is waxy and dull while that of Quartzite is vitreous. Chert is available in black, brown, green, grey, red, white colors whereas Quartzite is available in black, blue, brown, green, light grey, purple, white, yellow 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 Quartzite are an oil and gas reservoir, as armour rock for sea walls, cemetery markers, commemorative tablets, in aquifers, laboratory bench tops, petroleum reservoirs, soil conditioner, source of magnesia (mgo), tombstones, used in aquariums.