Definition
Felsite is a very fine grained volcanic rock that may or may not contain larger crystals and light colored rock that typically requires petrographic examination or chemical analysis for more precise definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Discoverer
Unknown
Van Tooren
Etymology
From English feldspar and -ite
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
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Arborescent Patterned, Vitreous
Aphanitic to Porphyritic
Color
Black, Blue, Brown, Green, Orange, Red, Tan, Yellow
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Vesicular
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
Arrowheads, Cutting Tool, Knives, Scrapers, Spear Points
Landscaping
Medical Industry
Surgery
-
Antiquity Uses
Artifacts
Artifacts, Sculpture
Commercial Uses
Mirror, Jewelry
Production of Lime, Soil Conditioner
Types
Igneous rock
Igneous rock
Features
Available in Lots of Colors and Patterns, Clasts are smooth to touch, Splintery, Very fine grained rock
Host Rock for Lead
Archaeological Significance
Formation
Felsite 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, Iron Oxides
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Contact 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, Glacier Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
Conchoidal
Uneven
Streak
White
Bluish Black
Porosity
Very Less Porous
Very Less Porous
Luster
Vitreous
Subvitreous to Dull
Cleavage
-
Crenulation and Pervasive
Specific Gravity
2.6-2.7
2.86
Transparency
Translucent
Opaque
Density
2.6 g/cm3
2.8-2.9 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Indonesia, Japan, Russia
-
Africa
Kenya
Namibia, Uganda
Europe
Greece, Hungary, Iceland, Italy, Turkey
Germany, Hungary, Italy, Portugal, Spain
Deposits in Western Continents
North America
Canada, Mexico, USA
USA
South America
Argentina, Chile, Ecuador, Peru
-
Deposits in Oceania Continent
Australia
New Zealand
New Zealand, Western Australia
All about Felsite and Tephrite Properties
Know all about Felsite and Tephrite properties here. All properties of rocks are important as they define the type of rock and its application. Felsite and Tephrite belong to Igneous Rocks.Texture of Felsite is Arborescent Patterned, Vitreous whereas that of Tephrite is Aphanitic to Porphyritic. Felsite appears Layered, Banded, Veined and Shiny and Tephrite appears Vesicular. The luster of Felsite is vitreous while that of Tephrite is subvitreous to dull. Felsite is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Tephrite is available in black, brown, green, grey, white colors. The commercial uses of Felsite are mirror, jewelry and that of Tephrite are production of lime, soil conditioner.