Definition
Tachylite is a vitreous form of basaltic volcanic glass. This glass is formed naturally by the rapid cooling of molten basalt
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Discoverer
Unknown
Van Tooren
Etymology
From German Tachylite, from tachy- + Greek lutos soluble, melting
From Greek tephra, ashes from Indo-European base, to burn
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Vitreous
Aphanitic to Porphyritic
Color
Black, Dark Brown
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Appearance
Glassy
Vesicular
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
Cutting Tool, Knives, Landscaping, Scrapers
Landscaping
Antiquity Uses
Artifacts
Artifacts, Sculpture
Commercial Uses
Cemetery Markers, Creating Artwork
Production of Lime, Soil Conditioner
Types
Volcanic glass
Igneous rock
Features
Available in Lots of Colors and Patterns, Clasts are smooth to touch
Host Rock for Lead
Archaeological Significance
Formation
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.
Tephrite 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
Feldspar, Olivine
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Compound Content
Fe, Mg
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Grain Size
Medium to Fine Coarse Grained
Medium to Fine Coarse Grained
Fracture
Conchoidal
Uneven
Streak
Vermilion
Bluish Black
Porosity
Less Porous
Very Less Porous
Luster
Resinous
Subvitreous to Dull
Cleavage
-
Crenulation and Pervasive
Specific Gravity
2.4
2.86
Transparency
Opaque
Opaque
Density
3.058 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Cambodia, Russia, South Korea
-
Africa
East Africa
Namibia, Uganda
Europe
England, Germany, Hungary, Iceland, Scotland, Sweden
Germany, Hungary, Italy, Portugal, Spain
Deposits in Western Continents
Deposits in Oceania Continent
Australia
Victoria
New Zealand, Western Australia