Definition
Icelandite belongs to volcanic igneous rocks which is rich in iron and belongs to andesite rock
  
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
  
History
  
  
Origin
Iceland
  
Germany
  
Discoverer
Ian S. E. Carmichael
  
Van Tooren
  
Etymology
From its origin place near Cenozoic volcano near the parsonage Þingmúli in East Iceland
  
From Greek tephra, ashes from Indo-European base, to burn
  
Class
Igneous Rocks
  
Igneous Rocks
  
Sub-Class
Durable Rock, Hard Rock
  
Durable Rock, Hard Rock
  
Family
  
  
Group
Volcanic
  
Volcanic
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Texture
Aphanitic to Porphyritic
  
Aphanitic to Porphyritic
  
Color
Bluish - Grey, Grey, Pink, Yellow
  
Black, Brown, Colourless, Green, Grey, White
  
Maintenance
More
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
No
  
No
  
Wind Resistant
Yes
  
Yes
  
Acid Resistant
No
  
No
  
Appearance
Dull and Soft
  
Vesicular
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration, Kitchens
  
Decorative Aggregates, Flooring, Homes, Interior Decoration
  
Exterior Uses
Office Buildings, Roof Tiles
  
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
Cobblestones, Construction Aggregate, for Road Aggregate
  
Landscaping
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Jewellery, Sculpture, Small Figurines
  
Artifacts, Sculpture
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Creating Artwork
  
Production of Lime, Soil Conditioner
  
Types
Not Available
  
Not Available
  
Features
Generally rough to touch, High silica content, Is one of the oldest rock
  
Host Rock for Lead
  
Archaeological Significance
  
  
Monuments
Not Yet Used
  
Not Yet Used
  
Famous Monuments
Not Applicable
  
Not Applicable
  
Sculpture
Used
  
Used
  
Famous Sculptures
Data Not Available
  
Data Not Available
  
Pictographs
Not Used
  
Not Used
  
Petroglyphs
Not Used
  
Not Used
  
Figurines
Used
  
Used
  
Fossils
Absent
  
Absent
  
Formation
Icelandite 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.
  
Composition
  
  
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Ilmenite, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
  
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
  
Compound Content
Silicon Dioxide
  
CaO, Carbon Dioxide, MgO, Silicon Dioxide
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Sea Erosion, Water Erosion, Wind Erosion
  
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
  
Physical Properties
  
  
Hardness
7
  
6.5
  
Grain Size
Very fine-grained
  
Medium to Fine Coarse Grained
  
Fracture
Uneven
  
Uneven
  
Streak
White
  
Bluish Black
  
Porosity
Less Porous
  
Very Less Porous
  
Luster
Vitreous
  
Subvitreous to Dull
  
Compressive Strength
Not Available
  
90.00 N/mm
2
  
22
Cleavage
Not Available
  
Crenulation and Pervasive
  
Toughness
1.1
  
2.4
  
Specific Gravity
2.5-2.8
  
2.86
  
Transparency
Opaque
  
Opaque
  
Density
2.11-2.36 g/cm3
  
2.8-2.9 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
2.39 kJ/Kg K
  
2
0.92 kJ/Kg K
  
10
Resistance
Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
  
Heat Resistant, Impact Resistant
  
Deposits in Eastern Continents
  
  
Asia
India, Indonesia, Japan, Nepal, South Korea
  
Not Yet Found
  
Africa
Egypt, Ethiopia, Morocco, Namibia, South Africa, Tanzania
  
Namibia, Uganda
  
Europe
Austria, Finland, Germany, Italy, Romania, Turkey, United Kingdom
  
Germany, Hungary, Italy, Portugal, Spain
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Mexico, USA
  
USA
  
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
  
Not Yet Found
  
Deposits in Oceania Continent
  
  
Australia
New South Wales, New Zealand, Western Australia
  
New Zealand, Western Australia
  
Icelandite vs Tephrite 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. Icelandite vs Tephrite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Icelandite and Properties of Tephrite. Learn more about Icelandite vs Tephrite in the next section. The interior uses of Icelandite include Decorative aggregates, Floor tiles, Homes, Interior decoration and Kitchens whereas the interior uses of Tephrite include Decorative aggregates, Flooring, Homes and Interior decoration. Due to some exceptional properties of Icelandite and Tephrite, they have various applications in construction industry. The uses of Icelandite in construction industry include Cobblestones, Construction aggregate, For road aggregate and that of Tephrite include Landscaping.
More about Icelandite and Tephrite
Here you can know more about Icelandite and Tephrite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Icelandite and Tephrite consists of mineral content and compound content. The mineral content of Icelandite includes Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Ilmenite, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon and mineral content of Tephrite includes Alkali feldspar, Nepheline, Plagioclase, Pyroxene. You can also check out the list of all Igneous Rocks. When we have to compare Icelandite vs Tephrite, the texture, color and appearance plays an important role in determining the type of rock. Icelandite is available in bluish - grey, grey, pink, yellow colors whereas, Tephrite is available in black, brown, colourless, green, grey, white colors. Appearance of Icelandite is Dull and Soft and that of Tephrite is Vesicular. Properties of rock is another aspect for Icelandite vs Tephrite. The hardness of Icelandite is 7 and that of Tephrite is 6.5. The types of Icelandite are Not Available whereas types of Tephrite are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Icelandite is white while that of Tephrite is bluish black. The specific heat capacity of Icelandite is 2.39 kJ/Kg K and that of Tephrite is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Icelandite is heat resistant, pressure resistant, scratch resistant, wear resistant whereas Tephrite is heat resistant, impact resistant.