Definition
Foidolite is a rare type of coarse-grained intrusive igneous rock with a feldspathoid mineral content greater than 60%
  
Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks
  
History
  
  
Discoverer
Unknown
  
Unknown
  
Etymology
From the mineral feldspathoid which is the main content of rock
  
From the Middle High German verb gneist (to spark; so called because the rock glitters)
  
Class
Igneous Rocks
  
Metamorphic Rocks
  
Sub-Class
Durable Rock, Soft Rock
  
Durable Rock, Hard Rock
  
Family
  
  
Group
Plutonic
  
Not Applicable
  
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
  
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
  
Texture
Earthy
  
Banded, Foliated, Platy
  
Color
Black, Brown, Colourless, Green, Grey, Pink, White
  
Black, Brown, Pink, Red, White
  
Maintenance
Less
  
More
  
Durability
Durable
  
Durable
  
Water Resistant
No
  
Yes
  
Scratch Resistant
No
  
Yes
  
Stain Resistant
No
  
Yes
  
Wind Resistant
No
  
Yes
  
Acid Resistant
No
  
No
  
Appearance
Dull
  
Foliated
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Interior Decoration
  
Countertops, Decorative Aggregates, Flooring, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
  
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
  
As Dimension Stone
  
Medical Industry
Taken as a Supplement for Calcium or Magnesium
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments, Sculpture
  
Artifacts
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
  
Cemetery Markers, Jewelry, Tombstones, Used in aquariums
  
Types
Not Available
  
Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.
  
Features
Host Rock for Lead
  
Generally rough to touch, Is one of the oldest rock
  
Archaeological Significance
  
  
Monuments
Used
  
Used
  
Famous Monuments
Data Not Available
  
Konark Sun Temple in India, Washington Monument, US
  
Sculpture
Used
  
Not Yet Used
  
Famous Sculptures
Data Not Available
  
Not Applicable
  
Pictographs
Used
  
Not Used
  
Petroglyphs
Used
  
Not Used
  
Figurines
Used
  
Not Yet Used
  
Fossils
Absent
  
Absent
  
Formation
Foidolites 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.
  
Gneiss is a high grade metamorphic rock i.e. it has been subjected to higher temperatures and pressures than schist. It is formed by the metamorphosis of Gneiss forms from volcanic rock, shale or granitie.
  
Composition
  
  
Mineral Content
Amphibole, Biotite, Feldspar, Olivine, Plagioclase, Pyroxene
  
Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon
  
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO
  
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
  
Impact Metamorphism
  
Weathering
No
  
Yes
  
Types of Weathering
Not Applicable
  
Biological Weathering, Mechanical Weathering
  
Erosion
No
  
Yes
  
Types of Erosion
Not Applicable
  
Chemical Erosion, Coastal Erosion, Sea Erosion
  
Physical Properties
  
  
Hardness
1.5
  
7
  
Grain Size
Medium to Fine Coarse Grained
  
Medium to Coarse Grained
  
Fracture
Conchoidal
  
Irregular
  
Streak
White
  
White
  
Porosity
Very Less Porous
  
Very Less Porous
  
Luster
Subvitreous to Dull
  
Dull
  
Compressive Strength
Not Available
  
125.00 N/mm
2
  
17
Cleavage
Perfect
  
Poor
  
Toughness
Not Available
  
1.2
  
Specific Gravity
2.86
  
2.5-2.7
  
Transparency
Translucent
  
Translucent to Opaque
  
Density
Not Available
  
2.6-2.9 g/cm3
  
Thermal Properties
  
  
Resistance
Heat Resistant, Wear Resistant
  
Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
  
Deposits in Eastern Continents
  
  
Asia
Russia
  
China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia
  
Africa
South Africa, Western Africa
  
Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo
  
Europe
Not Yet Found
  
Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine, United Kingdom
  
Others
Not Yet Found
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
Canada, Costa Rica, Cuba, Mexico, Panama, USA
  
South America
Not Yet Found
  
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
  
Deposits in Oceania Continent
  
  
Australia
Central Australia, Western Australia
  
New South Wales, New Zealand, Queensland, Victoria
  
Foidolite vs Gneiss 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. Foidolite vs Gneiss characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Foidolite and Properties of Gneiss. Learn more about Foidolite vs Gneiss in the next section. The interior uses of Foidolite include Decorative aggregates and Interior decoration whereas the interior uses of Gneiss include Countertops, Decorative aggregates, Flooring and Interior decoration. Due to some exceptional properties of Foidolite and Gneiss, they have various applications in construction industry. The uses of Foidolite in construction industry include As dimension stone, Cement manufacture, For road aggregate and that of Gneiss include As dimension stone.
More about Foidolite and Gneiss
Here you can know more about Foidolite and Gneiss. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Foidolite and Gneiss consists of mineral content and compound content. The mineral content of Foidolite includes Amphibole, Biotite, Feldspar, Olivine, Plagioclase, Pyroxene and mineral content of Gneiss includes Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon. You can also check out the list of all Igneous Rocks. When we have to compare Foidolite vs Gneiss, the texture, color and appearance plays an important role in determining the type of rock. Foidolite is available in black, brown, colourless, green, grey, pink, white colors whereas, Gneiss is available in black, brown, pink, red, white colors. Appearance of Foidolite is Dull and that of Gneiss is Foliated. Properties of rock is another aspect for Foidolite vs Gneiss. The hardness of Foidolite is 1.5 and that of Gneiss is 7. The types of Foidolite are Not Available whereas types of Gneiss are Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Foidolite and Gneiss is white. The specific heat capacity of Foidolite is Not Available and that of Gneiss is Not Available. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Foidolite is heat resistant, wear resistant whereas Gneiss is heat resistant, pressure resistant, scratch resistant, wear resistant.