Definition
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Siltstone can be defined as a fine-grained sedimentary rock which mainly consists of consolidated silt
Discoverer
Unknown
Unknown
Etymology
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
From English word silt and stone and from Proto-Indo-European root sal and stainaz
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Banded, Rough
Clastic
Color
Black, Brown, Green, Grey, Red, White
Brown, Red, Reddish Brown
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Glassy or Pearly
Rough
Interior Uses
Decorative Aggregates, Homes
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts, Monuments
Artifacts, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
Raw material for the manufacture of mortar, Soil Conditioner
Types
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Siltstone
Features
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Available in Lots of Colors and Patterns, Easily splits into thin plates, Generally rough to touch, High silica content, Very fine grained 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.
Siltstone is a type of sedimentary rock which is formed from fine rock particles. As the particles of eroded rock travel along with water, the edges of the rock are worn-out by water into a rounded shape.
Mineral Content
Quartz, Silicon
Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz, Sand, Silica, Silt
Compound Content
Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
-
-
Types of Weathering
-
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Very fine-grained
Fine Grained
Fracture
Uneven, Splintery or Conchoidal
Conchoidal
Porosity
Highly Porous
Highly Porous
Luster
Waxy and Dull
Dull
Specific Gravity
2.5-2.8
2.54-2.73
Transparency
Translucent to Opaque
Opaque
Density
2.7 g/cm3
2.6-2.7 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Water Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
Kenya, Morocco, South Africa, Tanzania
Namibia, Nigeria, South Africa
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Others
Greenland, Mid-Atlantic Ridge
Greenland
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Bolivia, Brazil
Brazil
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
New South Wales, New Zealand
Chert vs Siltstone 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 Siltstone characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Chert and Properties of Siltstone. Learn more about Chert vs Siltstone in the next section. The interior uses of Chert include Decorative aggregates and Homes whereas the interior uses of Siltstone include Decorative aggregates and Interior decoration. Due to some exceptional properties of Chert and Siltstone, 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 Siltstone include Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar.
More about Chert and Siltstone
Here you can know more about Chert and Siltstone. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Chert and Siltstone consists of mineral content and compound content. The mineral content of Chert includes Quartz, Silicon and mineral content of Siltstone includes Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz, Sand, Silica, Silt. You can also check out the list of all Sedimentary Rocks. When we have to compare Chert vs Siltstone, 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, Siltstone is available in brown, red, reddish brown colors. Appearance of Chert is Glassy or Pearly and that of Siltstone is Rough. Properties of rock is another aspect for Chert vs Siltstone. The hardness of Chert is 6.5-7 and that of Siltstone is 6-7. The types of Chert are Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter whereas types of Siltstone are Siltstone. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Chert and Siltstone is white. The specific heat capacity of Chert is 0.74 kJ/Kg K and that of Siltstone is 0.84 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 Siltstone is heat resistant, impact resistant, pressure resistant, water resistant.