Definition
Rapakivi Granite is a hornblende-biotite Granite containing large rounded crystals of orthoclase which are mantled with oligoclase
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
Jakob Sederholm
Unknown
Etymology
From Finnish Rapakivi which stands for crumbly 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, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Granular, Phaneritic
Banded, Foliated, Platy
Color
Black, Grey, Orange, Pink, White
Black, Brown, Pink, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Veined or Pebbled
Foliated
Interior Uses
Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Countertops, Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings, Paving Stone, Resorts
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
-
Curbing
Construction Industry
As Dimension Stone
As Dimension Stone
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Laboratory bench tops, Tombstones
Cemetery Markers, Jewelry, Tombstones, Used in aquariums
Types
Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite
Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.
Features
Available in Lots of Colors and Patterns, It is One of the Oldest, Strongest and Hardest Rock
Generally rough to touch, Is one of the oldest rock
Archaeological Significance
Famous Monuments
-
Konark Sun Temple in India, Washington Monument, US
Formation
Granite is an igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental 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.
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
Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Sea Erosion
Grain Size
Large and Coarse Grained
Medium to Coarse Grained
Porosity
Less Porous
Very Less Porous
Luster
Dull to Grainy with Sporadic parts Pearly and Vitreous
Dull
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
Resistance
Heat 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
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic
Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine, United Kingdom
Deposits in Western Continents
North America
Canada, USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
-
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
-
New South Wales, New Zealand, Queensland, Victoria
Rapakivi Granite 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. Rapakivi Granite vs Gneiss characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Rapakivi Granite and Properties of Gneiss. Learn more about Rapakivi Granite vs Gneiss in the next section. The interior uses of Rapakivi Granite include Bathrooms, Countertops, Decorative aggregates, Entryways, Floor tiles, Flooring, Homes, Hotels, Interior decoration, Kitchens and Stair treads whereas the interior uses of Gneiss include Countertops, Decorative aggregates, Flooring and Interior decoration. Due to some exceptional properties of Rapakivi Granite and Gneiss, they have various applications in construction industry. The uses of Rapakivi Granite in construction industry include As dimension stone and that of Gneiss include As dimension stone.
More about Rapakivi Granite and Gneiss
Here you can know more about Rapakivi Granite and Gneiss. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Rapakivi Granite and Gneiss consists of mineral content and compound content. The mineral content of Rapakivi Granite 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 Rapakivi Granite vs Gneiss, the texture, color and appearance plays an important role in determining the type of rock. Rapakivi Granite is available in black, grey, orange, pink, white colors whereas, Gneiss is available in black, brown, pink, red, white colors. Appearance of Rapakivi Granite is Veined or Pebbled and that of Gneiss is Foliated. Properties of rock is another aspect for Rapakivi Granite vs Gneiss. The hardness of Rapakivi Granite is 6-7 and that of Gneiss is 7. The types of Rapakivi Granite are Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite 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 Rapakivi Granite and Gneiss is white. The specific heat capacity of Rapakivi Granite is 0.79 kJ/Kg K and that of Gneiss is 0.70 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Rapakivi Granite is heat resistant, wear resistant whereas Gneiss is heat resistant, pressure resistant, scratch resistant, wear resistant.