Definition
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
History
Origin
Hawaii Islands
France
Discoverer
Unknown
Unknown
Etymology
From Greek pikros bitter + -ite, 19th century
From French, Latin lignum wood + -ite1
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
Family
Group
Volcanic
-
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Earthy, Rough
Amorphous, Glassy
Color
Black, Brown, Green, Grey, Pink, White, Yellow
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Rough and Shiny
Veined or Pebbled
Architecture
Interior Uses
Countertops, Decorative Aggregates, Homes, Interior Decoration
-
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
-
Other Architectural Uses
Curbing
-
Industry
Construction Industry
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.
for Road Aggregate, Steel Production
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture
-
Other Uses
Commercial Uses
As a Feed Additive for Livestock, As armour rock for sea walls, Metallurgical Flux, Pottery, Source of Magnesia (MgO)
Electricity Generation
Types
Oceanite
Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite
Features
Host Rock for Lead
Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Present
Formation
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.
Coal formation takes place due to accumulation of plant debris in a swamp environment. The Coal formation process continues, as peat turns into lignite brown or black coal at increasing heat and pressure.
Composition
Mineral Content
Biotite, Olivine, Plagioclase, Pyrrhotite
-
Compound Content
Al, CaO, Carbon Dioxide, Mg, MgO
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Impact Metamorphism, Regional Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
6.81
1
7
👆🏻
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
Uneven
Conchoidal
Streak
White, Greenish White or Grey
Black
Porosity
Less Porous
Highly Porous
Luster
Subvitreous to Dull
Dull to Vitreous to Submetallic
Compressive Strength
189.00 N/mm2-
0.15
450
👆🏻
Cleavage
-
-
Toughness
2.1
-
Specific Gravity
2.75-2.921.1-1.4
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
1.5-2.5 g/cm3800-801 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.88 kJ/Kg K1.26 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
India, Russia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
Africa
South Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Europe
Iceland
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
Others
-
-
Deposits in Western Continents
North America
Canada, USA
Canada, Mexico, USA
South America
Brazil
Brazil, Chile, Colombia, Venezuela
Deposits in Oceania Continent
Australia
-
New South Wales, Queensland, Victoria