Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
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 pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
From Old French pomis, from a Latin dialect variant of pumex
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Color
Black, Brown, Green, Grey, Pink, White
Beige, Grey, Light Green, Light Grey, Pink, White, Yellow- grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Vesicular
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing, Powder
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
As Dimension Stone, Cement Manufacture, for Road Aggregate, In landscaping and horticulture, Making natural cement, Production of lightweight concrete blocks
Medical Industry
-
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
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
Cataclastic rock
Scoria
Features
Host Rock for Lead
Host Rock for Lead
Archaeological Significance
Formation
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.
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
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Aluminum Oxides, Calcite, Carbonate, Iron Oxides, Silica
Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Al, Aluminium Oxide, CaO, Carbon Dioxide, MgO, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Impact Metamorphism
Types of Weathering
-
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
-
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Fine Grained
Streak
Light to dark brown
White, Greenish White or Grey
Porosity
Less Porous
Highly Porous
Specific Gravity
2.46-2.86
2.86
Transparency
Transparent to Translucent
Opaque
Density
2.7-2.9 g/cm3
0.25-0.3 g/cm3
Resistance
Heat Resistant
Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
South Korea
Afghanistan, Indonesia, Japan, Russia
Africa
Western Africa
Ethiopia, Kenya, Tanzania
Europe
Great Britain, Switzerland
Greece, Hungary, Iceland, Italy, Turkey
Deposits in Western Continents
North America
-
Bahamas, Barbados, Canada, Costa Rica, Cuba, Jamaica, Mexico, USA
South America
-
Argentina, Chile, Ecuador, Peru
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New Zealand, Western Australia
Pseudotachylite 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. Pseudotachylite vs Pumice characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Pseudotachylite and Properties of Pumice. Learn more about Pseudotachylite vs Pumice in the next section. The interior uses of Pseudotachylite include Decorative aggregates, Entryways and Interior decoration whereas the interior uses of Pumice include Decorative aggregates, Flooring, Homes and Interior decoration. Due to some exceptional properties of Pseudotachylite and Pumice, they have various applications in construction industry. The uses of Pseudotachylite in construction industry include As dimension stone, Cement manufacture, For road aggregate, Making natural cement 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 Pseudotachylite and Pumice
Here you can know more about Pseudotachylite and Pumice. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Pseudotachylite and Pumice consists of mineral content and compound content. The mineral content of Pseudotachylite includes Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides and mineral content of Pumice includes Aluminum Oxides, Calcite, Carbonate, Iron Oxides, Silica. You can also check out the list of all Metamorphic Rocks. When we have to compare Pseudotachylite vs Pumice, the texture, color and appearance plays an important role in determining the type of rock. Pseudotachylite is available in black, brown, green, grey, pink, white colors whereas, Pumice is available in beige, grey, light green, light grey, pink, white, yellow- grey colors. Appearance of Pseudotachylite is Dull and Soft and that of Pumice is Vesicular. Properties of rock is another aspect for Pseudotachylite vs Pumice. The hardness of Pseudotachylite is 7 and that of Pumice is 6. The types of Pseudotachylite are Cataclastic rock 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 Pseudotachylite is light to dark brown while that of Pumice is white, greenish white or grey. The specific heat capacity of Pseudotachylite is 0.92 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.Pseudotachylite is heat resistant whereas Pumice is impact resistant, pressure resistant.