Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
Tachylite is a vitreous form of basaltic volcanic glass. This glass is formed naturally by the rapid cooling of molten basalt
Discoverer
Unknown
Unknown
Etymology
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
From German Tachylite, from tachy- + Greek lutos soluble, melting
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Color
Black, Brown, Green, Grey, Pink, White
Black, Dark Brown
Durability
Durable
Durable
Appearance
Dull and Soft
Glassy
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Decorative Aggregates, 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
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
Cutting Tool, Knives, Landscaping, Scrapers
Antiquity Uses
Artifacts, Monuments
Artifacts
Commercial Uses
Creating Artwork, Gemstone
Cemetery Markers, Creating Artwork
Types
Cataclastic rock
Volcanic glass
Features
Host Rock for Lead
Available in Lots of Colors and Patterns, Clasts are smooth to touch
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.
Tachylite 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.
Mineral Content
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Feldspar, Olivine
Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Fe, Mg
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
-
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
-
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Medium to Fine Coarse Grained
Fracture
Uneven
Conchoidal
Streak
Light to dark brown
Vermilion
Porosity
Less Porous
Less Porous
Specific Gravity
2.46-2.86
2.4
Transparency
Transparent to Translucent
Opaque
Density
2.7-2.9 g/cm3
3.058 g/cm3
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
South Korea
Cambodia, Russia, South Korea
Africa
Western Africa
East Africa
Europe
Great Britain, Switzerland
England, Germany, Hungary, Iceland, Scotland, Sweden
Deposits in Western Continents
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
Victoria
Pseudotachylite vs Tachylite 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 Tachylite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Pseudotachylite and Properties of Tachylite. Learn more about Pseudotachylite vs Tachylite in the next section. The interior uses of Pseudotachylite include Decorative aggregates, Entryways and Interior decoration whereas the interior uses of Tachylite include Decorative aggregates and Interior decoration. Due to some exceptional properties of Pseudotachylite and Tachylite, 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 Tachylite include Cutting tool, Knives, Landscaping, Scrapers.
More about Pseudotachylite and Tachylite
Here you can know more about Pseudotachylite and Tachylite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Pseudotachylite and Tachylite consists of mineral content and compound content. The mineral content of Pseudotachylite includes Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides and mineral content of Tachylite includes Feldspar, Olivine. You can also check out the list of all Metamorphic Rocks. When we have to compare Pseudotachylite vs Tachylite, 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, Tachylite is available in black, dark brown colors. Appearance of Pseudotachylite is Dull and Soft and that of Tachylite is Glassy. Properties of rock is another aspect for Pseudotachylite vs Tachylite. The hardness of Pseudotachylite is 7 and that of Tachylite is 5.5. The types of Pseudotachylite are Cataclastic rock whereas types of Tachylite are Volcanic glass. 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 Tachylite is vermilion. The specific heat capacity of Pseudotachylite is 0.92 kJ/Kg K and that of Tachylite is 0.56 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 Tachylite is heat resistant, impact resistant, wear resistant.