Definition
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Flint is a hard type of sedimentary rock that produces a small piece of burning material when hit by steel
History
Origin
Germany
-
Discoverer
Van Tooren
Unknown
Etymology
From Greek tephra, ashes from Indo-European base, to burn
From Old English flint - a type of rock mainly known for high hardness and for giving off sparks when struck
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
Volcanic
-
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Banded, Rough
Color
Black, Brown, Green, Grey, White
Black, Brown, Green, Grey, Red, White
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Vesicular
Glassy or Pearly
Architecture
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
Landscaping
Arrowheads, Cutting Tool, Spear Points
Medical Industry
-
-
Antiquity Uses
Artifacts, Sculpture
Artifacts
Other Uses
Commercial Uses
Production of Lime, Soil Conditioner
Creating Artwork, Gemstone, In fire-starting tools, Manufacture of tools, Metallurgical Flux, Jewelry, To ignite fire, Used in flintlock firearms
Types
Igneous rock
Chert and Jasper
Features
Host Rock for Lead
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
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.
Flint is formed by the decomposition and compaction of various organisms such as sponges and diatoms under the water.
Composition
Mineral Content
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Silicon
Compound Content
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Physical Properties
Hardness
6.57
1
7
👆🏻
Grain Size
Medium to Fine Coarse Grained
Very fine-grained
Fracture
Uneven
Conchoidal
Streak
Bluish Black
White
Porosity
Very Less Porous
Highly Porous
Luster
Subvitreous to Dull
Vitreous
Compressive Strength
90.00 N/mm2450.00 N/mm2
0.15
450
👆🏻
Cleavage
Crenulation and Pervasive
-
Toughness
2.4
1.5
Specific Gravity
2.862.5-2.8
0
8.4
👆🏻
Transparency
Opaque
Translucent to Opaque
Density
2.8-2.9 g/cm32.7-2.71 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.92 kJ/Kg K0.74 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
-
Azerbaijan, China, Russia
Africa
Namibia, Uganda
-
Europe
Germany, Hungary, Italy, Portugal, Spain
Austria, Belgium, Cyprus, Denmark, France, Germany, Italy, Malta, Netherlands, Poland, Portugal, Romania, Spain, Sweden, Switzerland, Turkey, Ukraine, United Kingdom
Others
-
-
Deposits in Western Continents
North America
USA
USA
South America
-
Bolivia
Deposits in Oceania Continent
Australia
New Zealand, Western Australia
New Zealand, South Australia