Definition
Rapakivi Granite is a hornblende-biotite Granite containing large rounded crystals of orthoclase which are mantled with oligoclase
Very fine grained fault rock which is composed of glassy matrix that often contains inclusions of wall-rock fragments.
Origin
Finland, Europe
USA
Discoverer
Jakob Sederholm
Unknown
Etymology
From Finnish Rapakivi which stands for crumbly rock
From pseudo- + tachylite, a glassy rock generated by frictional heat within faults.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Granular, Phaneritic
Quench
Color
Black, Grey, Orange, Pink, White
Black, Brown, Green, Grey, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Veined or Pebbled
Dull and Soft
Interior Uses
Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings, Paving Stone, Resorts
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
-
Curbing
Construction Industry
As Dimension Stone
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Laboratory bench tops, Tombstones
Creating Artwork, Gemstone
Types
Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite
Cataclastic rock
Features
Available in Lots of Colors and Patterns, It is One of the Oldest, Strongest and Hardest Rock
Host Rock for Lead
Archaeological Significance
Formation
Granite is an igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Pseudotachylite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Carbon Dioxide, Silicon Dioxide, Sulfur Dioxide, Sulphur
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
-
Grain Size
Large and Coarse Grained
Very fine-grained
Streak
White
Light to dark brown
Porosity
Less Porous
Less Porous
Luster
Dull to Grainy with Sporadic parts Pearly and Vitreous
Vitreous
Specific Gravity
2.6-2.7
2.46-2.86
Transparency
Opaque
Transparent to Translucent
Density
2.6-2.8 g/cm3
2.7-2.9 g/cm3
Resistance
Heat Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
South Korea
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Western Africa
Europe
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic
Great Britain, Switzerland
Deposits in Western Continents
North America
Canada, USA
-
Deposits in Oceania Continent
Australia
-
Central Australia, Western Australia
Rapakivi Granite vs Pseudotachylite 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 Pseudotachylite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Rapakivi Granite and Properties of Pseudotachylite. Learn more about Rapakivi Granite vs Pseudotachylite 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 Pseudotachylite include Decorative aggregates, Entryways and Interior decoration. Due to some exceptional properties of Rapakivi Granite and Pseudotachylite, they have various applications in construction industry. The uses of Rapakivi Granite in construction industry include As dimension stone and that of Pseudotachylite include As dimension stone, Cement manufacture, For road aggregate, Making natural cement.
More about Rapakivi Granite and Pseudotachylite
Here you can know more about Rapakivi Granite and Pseudotachylite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Rapakivi Granite and Pseudotachylite 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 Pseudotachylite includes Iron Oxides, Pyroxene, Quartz, Stishovite, Sulfides. You can also check out the list of all Igneous Rocks. When we have to compare Rapakivi Granite vs Pseudotachylite, 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, Pseudotachylite is available in black, brown, green, grey, pink, white colors. Appearance of Rapakivi Granite is Veined or Pebbled and that of Pseudotachylite is Dull and Soft. Properties of rock is another aspect for Rapakivi Granite vs Pseudotachylite. The hardness of Rapakivi Granite is 6-7 and that of Pseudotachylite is 7. The types of Rapakivi Granite are Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite whereas types of Pseudotachylite are Cataclastic rock. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Rapakivi Granite is white while that of Pseudotachylite is light to dark brown. The specific heat capacity of Rapakivi Granite is 0.79 kJ/Kg K and that of Pseudotachylite 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.Rapakivi Granite is heat resistant, wear resistant whereas Pseudotachylite is heat resistant.