Definition
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
An iron rich extrusive rock found as a member of the alkali basalt magma series
Origin
USA
Isle of Mull, Scotland
Discoverer
Unknown
Ben More
Etymology
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
From the name of discoverer, Ben More
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
Texture
Quench
Glassy, Massive, Porphyritic, Scoriaceous, Trachytic, Vesicular
Color
Black, Brown, Green, Grey, Pink, White
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull and Soft
Rough and Dull
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Floor Tiles, Homes, Hotels, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Antiquity Uses
Artifacts, Monuments
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Gemstone
Commemorative Tablets, Creating Artwork, Curling
Types
Cataclastic rock
Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB) and Tholeiitic Basalt
Features
Host Rock for Lead
Has High structural resistance against erosion and climate, Very fine grained rock
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.
Benmoreite is a type of Igneous rock which is formed through the cooling and solidification of lava or magma. 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
Alkali feldspar, Biotite, Olivine, Plagioclase, Pyroxene, Sodic plagioclase
Compound Content
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
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, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Fine Grained
Fracture
Uneven
Conchoidal
Streak
Light to dark brown
Black
Porosity
Less Porous
Less Porous
Specific Gravity
2.46-2.86
2.8-3
Transparency
Transparent to Translucent
Opaque
Density
2.7-2.9 g/cm3
2.9-3.1 g/cm3
Resistance
Heat Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
South Korea
India, Russia
Africa
Western Africa
South Africa
Europe
Great Britain, Switzerland
Iceland
Deposits in Western Continents
North America
-
Canada, USA
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
-
All about Pseudotachylite and Benmoreite Properties
Know all about Pseudotachylite and Benmoreite properties here. All properties of rocks are important as they define the type of rock and its application. Pseudotachylite belongs to Metamorphic Rocks while Benmoreite belongs to Igneous Rocks.Texture of Pseudotachylite is Quench whereas that of Benmoreite is Glassy, Massive, Porphyritic, Scoriaceous, Trachytic, Vesicular. Pseudotachylite appears Dull and Soft and Benmoreite appears Rough and Dull. The luster of Pseudotachylite is vitreous while that of Benmoreite is earthy. Pseudotachylite is available in black, brown, green, grey, pink, white colors whereas Benmoreite is available in black, brown, light to dark grey colors. The commercial uses of Pseudotachylite are creating artwork, gemstone and that of Benmoreite are commemorative tablets, creating artwork, curling.