Definition
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Pumice is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals
Discoverer
Unknown
Unknown
Etymology
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
From Old French pomis, from a Latin dialect variant of pumex
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Banded, Rough
Vesicular
Color
Black, Brown, Green, Grey, Red, White
Beige, Colourless, Grey, Light Green, Light Grey, Pink, White, Yellow- grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Glassy or Pearly
Vesicular
Interior Uses
Decorative Aggregates, Homes
Decorative Aggregates, Flooring, Homes, Interior Decoration
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, Powder
Construction Industry
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
As Dimension Stone, Cement Manufacture, for Road Aggregate, In landscaping and horticulture, Making natural cement, Production of lightweight concrete blocks
Medical Industry
Not Yet Used
As an abrasive in skin exfoliating products, In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
Antiquity Uses
Artifacts, Monuments
Artifacts
Commercial Uses
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
As a traction material on snow-covered roads, As an abrasive in pencil erasers, Fine abrasive used for polishing, Manufacture of Soap, Solvents, Dyes, Plastics and Fibres, Used in aquariums
Types
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Scoria
Features
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Host Rock for Lead
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
Sculpture
Not Yet Used
Not Yet Used
Famous Sculptures
Not Applicable
Not Applicable
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Figurines
Not Yet Used
Not Yet Used
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.
Pumice rock forms when the magma cools so quickly that atoms in the melt are not able to arrange themselves into a crystalline structure.
Mineral Content
Quartz, Silicon
Aluminum Oxides, Calcite, Carbonate, Iron Oxides, Silica
Compound Content
Silicon Dioxide
Al, Aluminium Oxide, CaO, Carbon Dioxide, MgO, Silicon Dioxide
Types of Metamorphism
Not Applicable
Burial Metamorphism, Impact Metamorphism
Types of Weathering
Not Applicable
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Fine Grained
Fracture
Uneven, Splintery or Conchoidal
Planar
Streak
White
White, Greenish White or Grey
Porosity
Highly Porous
Highly Porous
Luster
Waxy and Dull
Earthy
Cleavage
Non-Existent
Perfect
Specific Gravity
2.5-2.8
2.86
Transparency
Translucent to Opaque
Opaque
Density
2.7 g/cm3
0.25-0.3 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Afghanistan, Indonesia, Japan, Russia
Africa
Kenya, Morocco, South Africa, Tanzania
Ethiopia, Kenya, Tanzania
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Greece, Hungary, Iceland, Italy, Turkey
Others
Greenland, Mid-Atlantic Ridge
Not Yet Found
Deposits in Western Continents
North America
Canada, Mexico, USA
Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA
South America
Bolivia, Brazil
Argentina, Chile, Ecuador, Peru
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
New Zealand, Western Australia
Chert vs Pumice 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 Pumice characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Chert and Properties of Pumice. Learn more about Chert vs Pumice in the next section. The interior uses of Chert include Decorative aggregates and Homes whereas the interior uses of Pumice include Decorative aggregates, Flooring, Homes and Interior decoration. Due to some exceptional properties of Chert and Pumice, 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 Pumice include As dimension stone, Cement manufacture, For road aggregate, In landscaping and horticulture, Making natural cement, Production of lightweight concrete blocks.
More about Chert and Pumice
Here you can know more about Chert and Pumice. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Chert and Pumice consists of mineral content and compound content. The mineral content of Chert includes Quartz, Silicon and mineral content of Pumice includes Aluminum Oxides, Calcite, Carbonate, Iron Oxides, Silica. You can also check out the list of all Sedimentary Rocks. When we have to compare Chert vs Pumice, 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, Pumice is available in beige, colourless, grey, light green, light grey, pink, white, yellow- grey colors. Appearance of Chert is Glassy or Pearly and that of Pumice is Vesicular. Properties of rock is another aspect for Chert vs Pumice. The hardness of Chert is 6.5-7 and that of Pumice is 6. The types of Chert are Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter whereas types of Pumice are Scoria. 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 Pumice is white, greenish white or grey. The specific heat capacity of Chert is 0.74 kJ/Kg K and that of Pumice is 0.87 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 Pumice is impact resistant, pressure resistant.