Definition
Pumice is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
Discoverer
Unknown
Unknown
Etymology
From Old French pomis, from a Latin dialect variant of pumex
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Color
Beige, Grey, Light Green, Light Grey, Pink, White, Yellow- grey
Black, Brown, Green, Grey, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Vesicular
Dull and Soft
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
Curbing, Powder
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, In landscaping and horticulture, Making natural cement, Production of lightweight concrete blocks
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
Medical Industry
As an abrasive in skin exfoliating products, In Chemical and Pharmaceutical Industry, Medicines and Cosmetics
-
Antiquity Uses
Artifacts
Artifacts, Monuments
Commercial Uses
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
Creating Artwork, Gemstone
Types
Scoria
Cataclastic rock
Features
Host Rock for Lead
Host Rock for Lead
Archaeological Significance
Formation
Pumice rock forms when the magma cools so quickly that atoms in the melt are not able to arrange themselves into a crystalline structure.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Pseudotachylite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Aluminum Oxides, Calcite, Carbonate, Iron Oxides, Silica
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Compound Content
Al, Aluminium Oxide, CaO, Carbon Dioxide, MgO, Silicon Dioxide
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Types of Metamorphism
Burial Metamorphism, Impact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
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Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
-
Grain Size
Fine Grained
Very fine-grained
Streak
White, Greenish White or Grey
Light to dark brown
Porosity
Highly Porous
Less Porous
Specific Gravity
2.86
2.46-2.86
Transparency
Opaque
Transparent to Translucent
Density
0.25-0.3 g/cm3
2.7-2.9 g/cm3
Resistance
Impact Resistant, Pressure Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
South Korea
Africa
Ethiopia, Kenya, Tanzania
Western Africa
Europe
Greece, Hungary, Iceland, Italy, Turkey
Great Britain, Switzerland
Deposits in Western Continents
North America
Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA
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South America
Argentina, Chile, Ecuador, Peru
-
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
Central Australia, Western Australia
All about Pumice and Pseudotachylite Properties
Know all about Pumice and Pseudotachylite properties here. All properties of rocks are important as they define the type of rock and its application. Pumice belongs to Igneous Rocks while Pseudotachylite belongs to Metamorphic Rocks.Texture of Pumice is Vesicular whereas that of Pseudotachylite is Quench. Pumice appears Vesicular and Pseudotachylite appears Dull and Soft. The luster of Pumice is earthy while that of Pseudotachylite is vitreous. Pumice is available in beige, grey, light green, light grey, pink, white, yellow- grey colors whereas Pseudotachylite is available in black, brown, green, grey, pink, white colors. The commercial uses of Pumice are 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 and that of Pseudotachylite are creating artwork, gemstone.