Definition
Basalt is a common extrusive igneous rock formed by the rapid cooling of basaltic lava exposed at or very near the surface of Earth
Tachylite is a vitreous form of basaltic volcanic glass. This glass is formed naturally by the rapid cooling of molten basalt
Discoverer
Georgius Agricola
Unknown
Etymology
From Late Latin Basaltes (variant of basanites ), very hard stone, which was imported from Ancient Greek Basanites
From German Tachylite, from tachy- + Greek lutos soluble, melting
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Vitreous
Color
Black, Brown, Light to Dark Grey
Black, Dark Brown
Durability
Durable
Durable
Appearance
Dull and Soft
Glassy
Interior Uses
Floor Tiles, Homes, Hotels, Kitchens
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing, Whetstones
Curbing
Construction Industry
Arrowheads, As Dimension Stone, Cobblestones, Cutting Tool, Rail Track Ballast, Roadstone
Cutting Tool, Knives, Landscaping, Scrapers
Antiquity Uses
Artifacts, Monuments
Artifacts
Commercial Uses
An Oil and Gas Reservoir, Commemorative Tablets, Creating Artwork, Used in aquariums
Cemetery Markers, Creating Artwork
Types
Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite
Volcanic glass
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Available in Lots of Colors and Patterns, Clasts are smooth to touch
Archaeological Significance
Famous Monuments
Easter Island in the Polynesian Triangle, Pacific Ocean, Gateway of India in Mumbai, India, Gol Gumbaz in Karnataka, India
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Formation
Basalt forms when lava reaches the Earth's surface near an active volcano. The temperature of lava is between 1100 to 1250° C when it gets to the surface.
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
Olivine, Plagioclase, Pyroxene
Feldspar, Olivine
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Fe, Mg
Types of Metamorphism
Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
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Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
Conchoidal
Conchoidal
Streak
White to Grey
Vermilion
Porosity
Less Porous
Less Porous
Specific Gravity
2.8-3
2.4
Transparency
Opaque
Opaque
Density
2.9-3.1 g/cm3
3.058 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
India, Russia
Cambodia, Russia, South Korea
Africa
South Africa
East Africa
Europe
Iceland
England, Germany, Hungary, Iceland, Scotland, Sweden
Deposits in Western Continents
North America
Canada, USA
USA
Deposits in Oceania Continent
Basalt 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. Basalt vs Tachylite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Basalt and Properties of Tachylite. Learn more about Basalt vs Tachylite in the next section. The interior uses of Basalt include Floor tiles, Homes, Hotels and Kitchens whereas the interior uses of Tachylite include Decorative aggregates and Interior decoration. Due to some exceptional properties of Basalt and Tachylite, they have various applications in construction industry. The uses of Basalt in construction industry include Arrowheads, As dimension stone, Cobblestones, Cutting tool, Rail track ballast, Roadstone and that of Tachylite include Cutting tool, Knives, Landscaping, Scrapers.
More about Basalt and Tachylite
Here you can know more about Basalt and Tachylite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Basalt and Tachylite consists of mineral content and compound content. The mineral content of Basalt includes Olivine, Plagioclase, Pyroxene and mineral content of Tachylite includes Feldspar, Olivine. You can also check out the list of all Igneous Rocks. When we have to compare Basalt vs Tachylite, the texture, color and appearance plays an important role in determining the type of rock. Basalt is available in black, brown, light to dark grey colors whereas, Tachylite is available in black, dark brown colors. Appearance of Basalt is Dull and Soft and that of Tachylite is Glassy. Properties of rock is another aspect for Basalt vs Tachylite. The hardness of Basalt is 6 and that of Tachylite is 5.5. The types of Basalt are Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite 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 Basalt is white to grey while that of Tachylite is vermilion. The specific heat capacity of Basalt is 0.84 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.Basalt is heat resistant, pressure resistant, wear resistant whereas Tachylite is heat resistant, impact resistant, wear resistant.