Definition
Phyllite is a fine-grained metamorphic rock with a well-developed laminar structure, and is intermediate between slate and schist rocks
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Discoverer
Unknown
Unknown
Etymology
From Greek phullon leaf + -ite1
From Greek pikros bitter + -ite, 19th century
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Phyllitic Sheen, Slaty
Earthy, Rough
Color
Black to Grey, Light Greenish Grey
Black, Brown, Green, Grey, Pink, White, Yellow
Durability
Durable
Durable
Appearance
Crinkled or Wavy
Rough and Shiny
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Interior Decoration
Countertops, Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar, Roadstone
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
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Writing Slates
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Features
Easily splits into thin plates, Is one of the oldest rock, Surfaces are often shiny
Host Rock for Lead
Archaeological Significance
Formation
Phyllite is a metamorphic rock which is formed by regional metamorphism of argillaceous sediments since their cleavage arose due to deviatoric stress.
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
Albite, Alusite, Amphibole, Apatite, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc, Zircon
Biotite, Olivine, Plagioclase, Pyrrhotite
Compound Content
CaO, Carbon Dioxide, MgO
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
Chemical Erosion, Coastal 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
Conchoidal
Uneven
Streak
White
White, Greenish White or Grey
Porosity
Highly Porous
Less Porous
Luster
Phyllitic
Subvitreous to Dull
Cleavage
Crenulation and Pervasive
-
Specific Gravity
2.72-2.73
2.75-2.92
Transparency
Opaque
Opaque
Density
2.18-3.3 g/cm3
1.5-2.5 g/cm3
Resistance
Heat Resistant, Pressure Resistant, Water Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
India, Russia
Africa
Egypt, Ethiopia, Morocco, Nigeria, South Africa
South Africa
Europe
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Iceland
Deposits in Western Continents
North America
Canada, Costa Rica, Cuba, Mexico, Panama, USA
Canada, USA
South America
Brazil, Colombia, Guyana
Brazil
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland
-
All about Phyllite and Picrite Properties
Know all about Phyllite and Picrite properties here. All properties of rocks are important as they define the type of rock and its application. Phyllite belongs to Metamorphic Rocks while Picrite belongs to Igneous Rocks.Texture of Phyllite is Phyllitic Sheen, Slaty whereas that of Picrite is Earthy, Rough. Phyllite appears Crinkled or Wavy and Picrite appears Rough and Shiny. The luster of Phyllite is phyllitic while that of Picrite is subvitreous to dull. Phyllite is available in black to grey, light greenish grey colors whereas Picrite is available in black, brown, green, grey, pink, white, yellow colors. The commercial uses of Phyllite are cemetery markers, commemorative tablets, creating artwork, writing slates and that of Picrite are as a feed additive for livestock, as armour rock for sea walls, metallurgical flux, pottery, source of magnesia (mgo).