Definition
Arkose is a sedimentary rock, specifically a type of sandstone containing at least 25% feldspar
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Origin
France
Hawaii Islands
Discoverer
Alexandre Brongniart
Unknown
Etymology
From Auvergne region of France used by a French geologist Alexandre Brongniart in 1826 who applied this term to some feldspathic sandstones
From Greek pikros bitter + -ite, 19th century
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic
Earthy, Rough
Color
Reddish Brown
Black, Brown, Green, Grey, Pink, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Rough and Dull
Rough and Shiny
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Countertops, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
Paving Stone, Office Buildings
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Whetstones
Curbing
Construction Industry
Cement Manufacture, Construction Aggregate, for Road Aggregate, Production of Glass and Ceramics, Raw material for the manufacture of mortar
As a Sintering Agent in Steel Industry to process Iron Ore, Cement Manufacture, for Road Aggregate, Manufacture of Magnesium and Dolomite Refractories, Roadstone, Used for flooring, stair treads, borders and window sills.
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
In aquifers, Soil Conditioner, Source of Magnesia (MgO), Tombstones
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Features
Available in Lots of Colors and Patterns, Generally rough to touch, Is one of the oldest rock
Host Rock for Lead
Archaeological Significance
Formation
Arkose rock forms from the weathering of feldspar-rich igneous or metamorphic rock, most commonly granitic rocks, which are primarily composed of quartz and feldspar.
Picrite 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.
Mineral Content
Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz
Biotite, Olivine, Plagioclase, Pyrrhotite
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
Al, CaO, Carbon Dioxide, Mg, MgO
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Coarse Grained
Fine Grained
Fracture
Conchoidal
Uneven
Streak
White
White, Greenish White or Grey
Porosity
Highly Porous
Less Porous
Luster
Dull
Subvitreous to Dull
Specific Gravity
0
2.75-2.92
Transparency
Opaque
Opaque
Density
-9999 g/cm3
1.5-2.5 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
India, Russia
Africa
Namibia, Nigeria, South Africa
South Africa
Europe
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Iceland
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand
-
Arkose vs Picrite 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. Arkose vs Picrite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Arkose and Properties of Picrite. Learn more about Arkose vs Picrite in the next section. The interior uses of Arkose include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Picrite include Countertops, Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Arkose and Picrite, they have various applications in construction industry. The uses of Arkose in construction industry include Cement manufacture, Construction aggregate, For road aggregate, Production of glass and ceramics, Raw material for the manufacture of mortar and that of Picrite include As a sintering agent in steel industry to process iron ore, Cement manufacture, For road aggregate, Manufacture of magnesium and dolomite refractories, Roadstone, Used for flooring, stair treads, borders and window sills..
More about Arkose and Picrite
Here you can know more about Arkose and Picrite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Arkose and Picrite consists of mineral content and compound content. The mineral content of Arkose includes Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz and mineral content of Picrite includes Biotite, Olivine, Plagioclase, Pyrrhotite. You can also check out the list of all Sedimentary Rocks. When we have to compare Arkose vs Picrite, the texture, color and appearance plays an important role in determining the type of rock. Arkose is available in reddish brown colors whereas, Picrite is available in black, brown, green, grey, pink, white, yellow colors. Appearance of Arkose is Rough and Dull and that of Picrite is Rough and Shiny. Properties of rock is another aspect for Arkose vs Picrite. The hardness of Arkose is 6-7 and that of Picrite is 6.8. The types of Arkose are Arkose whereas types of Picrite are Oceanite. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Arkose is white while that of Picrite is white, greenish white or grey. The specific heat capacity of Arkose is 0.78 kJ/Kg K and that of Picrite is 0.88 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Arkose is heat resistant, impact resistant, pressure resistant whereas Picrite is heat resistant.