Definition
Felsite is a very fine grained volcanic rock that may or may not contain larger crystals and light colored rock that typically requires petrographic examination or chemical analysis for more precise definition
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Discoverer
Unknown
Unknown
Etymology
From English feldspar and -ite
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Arborescent Patterned, Vitreous
Banded, Rough
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Black, Brown, Green, Grey, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Glassy or Pearly
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Homes
Exterior Uses
Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
Medical Industry
Surgery
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Antiquity Uses
Artifacts
Artifacts, Monuments
Commercial Uses
Mirror, Jewelry
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
Types
Igneous rock
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Features
Available in Lots of Colors and Patterns, Clasts are smooth to touch, Splintery, Very fine grained rock
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Archaeological Significance
Formation
Felsite 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.
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.
Mineral Content
Feldspar, Iron Oxides
Quartz, Silicon
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
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Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
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Types of Erosion
Chemical Erosion, Glacier Erosion, Water Erosion
Chemical Erosion
Grain Size
Fine Grained
Very fine-grained
Fracture
Conchoidal
Uneven, Splintery or Conchoidal
Porosity
Very Less Porous
Highly Porous
Luster
Vitreous
Waxy and Dull
Specific Gravity
2.6-2.7
2.5-2.8
Transparency
Translucent
Translucent to Opaque
Density
2.6 g/cm3
2.7 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Kenya
Kenya, Morocco, South Africa, Tanzania
Europe
Greece, Hungary, Iceland, Italy, Turkey
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
Canada, Mexico, USA
South America
Argentina, Chile, Ecuador, Peru
Bolivia, Brazil
Deposits in Oceania Continent
Australia
New Zealand
New South Wales, Queensland, South Australia, Western Australia
Felsite vs Chert 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. Felsite vs Chert characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Felsite and Properties of Chert. Learn more about Felsite vs Chert in the next section. The interior uses of Felsite include Decorative aggregates, Flooring and Interior decoration whereas the interior uses of Chert include Decorative aggregates and Homes. Due to some exceptional properties of Felsite and Chert, they have various applications in construction industry. The uses of Felsite in construction industry include Arrowheads, Cutting tool, Knives, Scrapers, Spear points and that of Chert include Arrowheads, Construction aggregate, Cutting tool, Spear points.
More about Felsite and Chert
Here you can know more about Felsite and Chert. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Felsite and Chert consists of mineral content and compound content. The mineral content of Felsite includes Feldspar, Iron Oxides and mineral content of Chert includes Quartz, Silicon. You can also check out the list of all Igneous Rocks. When we have to compare Felsite vs Chert, the texture, color and appearance plays an important role in determining the type of rock. Felsite is available in black, blue, brown, green, orange, red, tan, yellow colors whereas, Chert is available in black, brown, green, grey, red, white colors. Appearance of Felsite is Layered, Banded, Veined and Shiny and that of Chert is Glassy or Pearly. Properties of rock is another aspect for Felsite vs Chert. The hardness of Felsite is 5-5.5 and that of Chert is 6.5-7. The types of Felsite are Igneous rock whereas types of Chert are Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Felsite and Chert is white. The specific heat capacity of Felsite is 0.92 kJ/Kg K and that of Chert is 0.74 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Felsite is heat resistant, impact resistant whereas Chert is heat resistant, impact resistant, pressure resistant, wear resistant.