Definition
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Rapakivi Granite is a hornblende-biotite Granite containing large rounded crystals of orthoclase which are mantled with oligoclase
Origin
Unknown
Finland, Europe
Discoverer
Unknown
Jakob Sederholm
Etymology
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
From Finnish Rapakivi which stands for crumbly rock
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Group
Not Applicable
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Banded, Rough
Granular, Phaneritic
Color
Black, Brown, Green, Grey, Red, White
Black, Grey, Orange, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Glassy or Pearly
Veined or Pebbled
Interior Uses
Decorative Aggregates, Homes
Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Office Buildings, Paving Stone, Resorts
Other Architectural Uses
Curbing
Not Yet Used
Construction Industry
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
As Dimension Stone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Laboratory bench tops, Tombstones
Types
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite
Features
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Available in Lots of Colors and Patterns, It is One of the Oldest, Strongest and Hardest Rock
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Figurines
Not Yet Used
Used
Formation
Chert forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The chert formation can be either of chemical or biological origin.
Granite is an igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks
Mineral Content
Quartz, Silicon
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism
Types of Weathering
Not Applicable
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Large and Coarse Grained
Fracture
Uneven, Splintery or Conchoidal
Not Available
Porosity
Highly Porous
Less Porous
Luster
Waxy and Dull
Dull to Grainy with Sporadic parts Pearly and Vitreous
Cleavage
Non-Existent
Not Available
Toughness
1.5
Not Available
Specific Gravity
2.5-2.8
2.6-2.7
Transparency
Translucent to Opaque
Opaque
Density
2.7 g/cm3
2.6-2.8 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
Kenya, Morocco, South Africa, Tanzania
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic, Venezuela
Others
Greenland, Mid-Atlantic Ridge
Not Yet Found
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Bolivia, Brazil
Not Yet Found
Deposits in Oceania Continent
Australia
New South Wales, Queensland, South Australia, Western Australia
Not Yet Found
Chert vs Rapakivi Granite 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. Chert vs Rapakivi Granite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Chert and Properties of Rapakivi Granite. Learn more about Chert vs Rapakivi Granite in the next section. The interior uses of Chert include Decorative aggregates and Homes whereas the interior uses of Rapakivi Granite include Bathrooms, Countertops, Decorative aggregates, Entryways, Floor tiles, Flooring, Homes, Hotels, Interior decoration, Kitchens and Stair treads. Due to some exceptional properties of Chert and Rapakivi Granite, they have various applications in construction industry. The uses of Chert in construction industry include Arrowheads, Construction aggregate, Cutting tool, Spear points and that of Rapakivi Granite include As dimension stone.
More about Chert and Rapakivi Granite
Here you can know more about Chert and Rapakivi Granite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Chert and Rapakivi Granite consists of mineral content and compound content. The mineral content of Chert includes Quartz, Silicon and mineral content of Rapakivi Granite includes Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz. You can also check out the list of all Sedimentary Rocks. When we have to compare Chert vs Rapakivi Granite, the texture, color and appearance plays an important role in determining the type of rock. Chert is available in black, brown, green, grey, red, white colors whereas, Rapakivi Granite is available in black, grey, orange, pink, white colors. Appearance of Chert is Glassy or Pearly and that of Rapakivi Granite is Veined or Pebbled. Properties of rock is another aspect for Chert vs Rapakivi Granite. The hardness of Chert is 6.5-7 and that of Rapakivi Granite is 6-7. The types of Chert are Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter whereas types of Rapakivi Granite are Igneous Protolith Granite, Sedimentary Protolith Granite, Mantle Granite, Anorogenic Granite and Hybrid Granite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Chert and Rapakivi Granite is white. The specific heat capacity of Chert is 0.74 kJ/Kg K and that of Rapakivi Granite is 0.79 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Chert is heat resistant, impact resistant, pressure resistant, wear resistant whereas Rapakivi Granite is heat resistant, wear resistant.
