Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Charnockite is a variety of granite containing minerals like orthopyroxene, quartz, and feldspar
Origin
Germany
Tamil Nadu, India
Discoverer
Van Tooren
T. H. Holland
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From Job Charnock, an administtrator of East India Company
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Granular
Color
Black, Brown, Green, Grey, White
Black, Grey, Orange, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Vesicular
Veined or Pebbled
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Homes, Hotels, Kitchens, Stair Treads
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Bridges, Paving Stone, Garden Decoration, Office Buildings, Resorts
Other Architectural Uses
Curbing
Curbing
Construction Industry
Landscaping
As Dimension Stone
Antiquity Uses
Artifacts, Sculpture
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Production of Lime, Soil Conditioner
Curling, Gemstone, Laboratory bench tops, Tombstones
Types
Igneous rock
Enderbite
Features
Host Rock for Lead
Available in Lots of Colors and Patterns, It is One of the Oldest, Strongest and Hardest Rock
Archaeological Significance
Formation
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.
Charnockite is an intrusive igneous rock which is very hard and is formed due to weathering of existing rocks.
Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Olivine, Plagioclase, Pyroxene, Quartz
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Contact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Coarse Grained
Streak
Bluish Black
White
Porosity
Very Less Porous
Very Less Porous
Luster
Subvitreous to Dull
-
Cleavage
Crenulation and Pervasive
-
Specific Gravity
2.86
-9999
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
2.6 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Africa
Namibia, Uganda
East Africa, Ethiopia, Madagascar, Morocco, Mozambique
Europe
Germany, Hungary, Italy, Portugal, Spain
Albania, Romania, Scotland, United Kingdom
Deposits in Western Continents
South America
-
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
Central Australia, Western Australia