Definition
Syenite is a coarse-grained igneous rock which is composed mainly of alkali feldspar and various ferromagnesian minerals
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
Discoverer
Unknown
Unknown
Etymology
From French syénite, from Latin Syenites (lapis ) (stone) of Syene
From the Middle High German verb gneist (to spark; so called because the rock glitters)
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
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
Brown, Buff, Cream, Green, Grey, Pink, White
Black, Brown, Pink, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded and Foilated
Foliated
Interior Uses
Flooring, Homes, Hotels, Interior Decoration
Countertops, Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
As Dimension Stone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Commercial Uses
Cemetery Markers, Creating Artwork
Cemetery Markers, Jewelry, Tombstones, Used in aquariums
Types
Shonkinite
Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.
Features
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
Generally rough to touch, Is one of the oldest rock
Archaeological Significance
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
Formation
Syenites are formed due to alkaline igneous activities and are generally formed in thick continental crustal areas or in Cordilleran subduction zones.
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.
Mineral Content
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Sea Erosion
Grain Size
Medium to Fine Coarse Grained
Medium to Coarse Grained
Fracture
Not Available
Irregular
Porosity
Less Porous
Very Less Porous
Luster
Subvitreous to Dull
Dull
Toughness
Not Available
1.2
Specific Gravity
2.6-2.7
2.5-2.7
Transparency
Opaque
Translucent to Opaque
Density
2.6-2.8 g/cm3
2.6-2.9 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo
Europe
Bulgaria, England, Germany, Norway, Romania, Switzerland
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
USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
Brazil, Chile
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New Zealand, Queensland, South Australia, Western Australia
New South Wales, New Zealand, Queensland, Victoria
Syenite 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. Syenite vs Gneiss characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Syenite and Properties of Gneiss. Learn more about Syenite vs Gneiss in the next section. The interior uses of Syenite include Flooring, Homes, Hotels and Interior decoration whereas the interior uses of Gneiss include Countertops, Decorative aggregates, Flooring and Interior decoration. Due to some exceptional properties of Syenite and Gneiss, they have various applications in construction industry. The uses of Syenite in construction industry include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate, Landscaping, Making natural cement, Manufacture of magnesium and dolomite refractories and that of Gneiss include As dimension stone.
More about Syenite and Gneiss
Here you can know more about Syenite and Gneiss. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Syenite and Gneiss consists of mineral content and compound content. The mineral content of Syenite includes Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz 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 Syenite vs Gneiss, the texture, color and appearance plays an important role in determining the type of rock. Syenite is available in brown, buff, cream, green, grey, pink, white colors whereas, Gneiss is available in black, brown, pink, red, white colors. Appearance of Syenite is Banded and Foilated and that of Gneiss is Foliated. Properties of rock is another aspect for Syenite vs Gneiss. The hardness of Syenite is 5.5-6 and that of Gneiss is 7. The types of Syenite are Shonkinite 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 Syenite and Gneiss is white. The specific heat capacity of Syenite is 0.92 kJ/Kg K 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.Syenite is heat resistant, impact resistant, wear resistant whereas Gneiss is heat resistant, pressure resistant, scratch resistant, wear resistant.