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
  
History
  
  
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
  
Family
  
  
Group
Volcanic
  
Not Applicable
  
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
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
Yes
  
No
  
Acid Resistant
No
  
Yes
  
Appearance
Layered, Banded, Veined and Shiny
  
Glassy or Pearly
  
Architecture
  
  
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
  
Industry
  
  
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
  
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
  
Medical Industry
Surgery
  
Not Yet Used
  
Antiquity Uses
Artifacts
  
Artifacts, Monuments
  
Other Uses
  
  
Commercial Uses
Mirror, Jewelry
  
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
  
Types
Not Available
  
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
  
  
Monuments
Not Yet Used
  
Used
  
Famous Monuments
Not Applicable
  
Data Not Available
  
Sculpture
Not Yet Used
  
Not Yet Used
  
Famous Sculptures
Not Applicable
  
Not Applicable
  
Pictographs
Used
  
Not Used
  
Petroglyphs
Used
  
Not Used
  
Figurines
Not Yet Used
  
Not Yet Used
  
Fossils
Absent
  
Present
  
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.
  
Composition
  
  
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
  
Transformation
  
  
Metamorphism
Yes
  
No
  
Types of Metamorphism
Burial Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Not Applicable
  
Weathering
Yes
  
No
  
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Not Applicable
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Glacier Erosion, Water Erosion
  
Chemical Erosion
  
Physical Properties
  
  
Hardness
5-5.5
  
6.5-7
  
Grain Size
Fine Grained
  
Very fine-grained
  
Fracture
Conchoidal
  
Uneven, Splintery or Conchoidal
  
Streak
White
  
White
  
Porosity
Very Less Porous
  
Highly Porous
  
Luster
Vitreous
  
Waxy and Dull
  
Compressive Strength
450.00 N/mm2
  
1
Cleavage
Non-Existent
  
Non-Existent
  
Toughness
Not Available
  
1.5
  
Specific Gravity
2.6-2.7
  
2.5-2.8
  
Transparency
Translucent
  
Translucent to Opaque
  
Density
2.6 g/cm3
  
2.7 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
0.92 kJ/Kg K
  
10
0.74 kJ/Kg K
  
19
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
Not Yet Found
  
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
  
All about Felsite and Chert Properties
Know all about Felsite and Chert properties here. All properties of rocks are important as they define the type of rock and its application. Felsite belongs to Igneous Rocks while Chert belongs to Sedimentary Rocks.Texture of Felsite is Arborescent Patterned, Vitreous whereas that of Chert is Banded, Rough. Felsite appears Layered, Banded, Veined and Shiny and Chert appears Glassy or Pearly. The luster of Felsite is vitreous while that of Chert is waxy and dull. 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. The commercial uses of Felsite are mirror, jewelry and that of Chert are creating artwork, gemstone, in fire-starting tools, jewelry, to ignite fire, used in flintlock firearms.