Definition
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Norite is a mafic intrusive igneous rock composed largely of the calcium-rich plagioclase labradorite, orthopyroxene, and olivine
Discoverer
Unknown
Unknown
Etymology
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
From the Norwegian name for Norway, Norge
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Banded, Rough
Phaneritic
Color
Black, Brown, Green, Grey, Red, White
Dark Grey to Black
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Glassy or Pearly
Veined and Shiny
Interior Uses
Decorative Aggregates, Homes
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts, Monuments
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Types
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Ultramafic intrusive rock
Features
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Smooth to touch
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.
Norite is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Mineral Content
Quartz, Silicon
Augite, Olivine, Plagioclase, Pyroxene
Compound Content
Silicon Dioxide
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Types of Metamorphism
-
Cataclastic Metamorphism, Impact Metamorphism
Types of Weathering
-
Biological Weathering
Types of Erosion
Chemical Erosion
Chemical Erosion, Coastal Erosion
Grain Size
Very fine-grained
Coarse Grained
Fracture
Uneven, Splintery or Conchoidal
Conchoidal
Porosity
Highly Porous
Highly Porous
Specific Gravity
2.5-2.8
2.86-2.87
Transparency
Translucent to Opaque
Opaque
Density
2.7 g/cm3
2.7-3.3 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
India, Russia
Africa
Kenya, Morocco, South Africa, Tanzania
South Africa
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Germany, Greece, Italy, Scotland, Turkey
Others
Greenland, Mid-Atlantic Ridge
Greenland
Deposits in Western Continents
North America
Canada, Mexico, USA
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
Chert vs Norite 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. Chert vs Norite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Chert and Properties of Norite. Learn more about Chert vs Norite in the next section. The interior uses of Chert include Decorative aggregates and Homes whereas the interior uses of Norite include Decorative aggregates, Entryways and Interior decoration. Due to some exceptional properties of Chert and Norite, they have various applications in construction industry. The uses of Chert in construction industry include Arrowheads, Construction aggregate, Cutting tool, Spear points and that of Norite include As dimension stone, Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate.
More about Chert and Norite
Here you can know more about Chert and Norite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Chert and Norite consists of mineral content and compound content. The mineral content of Chert includes Quartz, Silicon and mineral content of Norite includes Augite, Olivine, Plagioclase, Pyroxene. You can also check out the list of all Sedimentary Rocks. When we have to compare Chert vs Norite, the texture, color and appearance plays an important role in determining the type of rock. Chert is available in black, brown, green, grey, red, white colors whereas, Norite is available in dark grey to black colors. Appearance of Chert is Glassy or Pearly and that of Norite is Veined and Shiny. Properties of rock is another aspect for Chert vs Norite. The hardness of Chert is 6.5-7 and that of Norite is 7. The types of Chert are Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter whereas types of Norite are Ultramafic intrusive rock. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Chert is white while that of Norite is black. The specific heat capacity of Chert is 0.74 kJ/Kg K and that of Norite is 0.52 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Chert is heat resistant, impact resistant, pressure resistant, wear resistant whereas Norite is impact resistant, pressure resistant, wear resistant.