Definition
Migmatite is typically a granitic rock within a metamorphic host rock which is composed of two intermingled but distinguishable components
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Origin
Southern Alps, France
Hawaii Islands
Discoverer
Jakob Sederholm
Unknown
Etymology
From the Greek word migma which means a mixture
From Greek pikros bitter + -ite, 19th century
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated
Earthy, Rough
Color
Black, Bluish - Grey, Brown, Brown- Black, Dark Greenish - Grey, Dark Grey to Black
Black, Brown, Green, Grey, Pink, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull, Banded and Foilated
Rough and Shiny
Interior Uses
Countertops, Flooring, Kitchens
Countertops, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement
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
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Jewelry, Tombstones, Used to manufracture paperweights and bookends
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Types
Diatexites and Metatexites
Oceanite
Features
Generally rough to touch, Is one of the oldest rock
Host Rock for Lead
Archaeological Significance
Formation
Migmatites form by high temperature regional and thermal metamorphism of protolith rocks where rocks melt partially due to high temperature.
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
Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon
Biotite, Olivine, Plagioclase, Pyrrhotite
Compound Content
Aluminium Oxide, NaCl, CaO, Carbon Dioxide, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Al, CaO, Carbon Dioxide, Mg, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Irregular
Uneven
Streak
White
White, Greenish White or Grey
Porosity
Very Less Porous
Less Porous
Luster
Dull to Pearly to Subvitreous
Subvitreous to Dull
Specific Gravity
2.65-2.75
2.75-2.92
Transparency
Opaque
Opaque
Density
-9999 g/cm3
1.5-2.5 g/cm3
Resistance
Heat Resistant, Pressure Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia
India, Russia
Africa
Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo
South Africa
Europe
Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Sweden, Switzerland, Ukraine, United Kingdom
Iceland
Deposits in Western Continents
North America
Canada, Costa Rica, Cuba, Mexico, Panama, USA
Canada, USA
South America
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria
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Migmatite 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. Migmatite vs Picrite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Migmatite and Properties of Picrite. Learn more about Migmatite vs Picrite in the next section. The interior uses of Migmatite include Countertops, Flooring and Kitchens whereas the interior uses of Picrite include Countertops, Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Migmatite and Picrite, they have various applications in construction industry. The uses of Migmatite in construction industry include As dimension stone, Cement manufacture, For road aggregate, Making natural cement 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 Migmatite and Picrite
Here you can know more about Migmatite and Picrite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Migmatite and Picrite consists of mineral content and compound content. The mineral content of Migmatite includes Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon and mineral content of Picrite includes Biotite, Olivine, Plagioclase, Pyrrhotite. You can also check out the list of all Metamorphic Rocks. When we have to compare Migmatite vs Picrite, the texture, color and appearance plays an important role in determining the type of rock. Migmatite is available in black, bluish - grey, brown, brown- black, dark greenish - grey, dark grey to black colors whereas, Picrite is available in black, brown, green, grey, pink, white, yellow colors. Appearance of Migmatite is Dull, Banded and Foilated and that of Picrite is Rough and Shiny. Properties of rock is another aspect for Migmatite vs Picrite. The hardness of Migmatite is 5.5-6.5 and that of Picrite is 6.8. The types of Migmatite are Diatexites and Metatexites 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 Migmatite is white while that of Picrite is white, greenish white or grey. The specific heat capacity of Migmatite is 0.79 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.Migmatite is heat resistant, pressure resistant whereas Picrite is heat resistant.