Definition
Lignite is a soft brownish coal which shows traces of plants and is intermediate between bituminous coal and peat
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Discoverer
Unknown
Unknown
Etymology
From French, Latin lignum wood + -ite1
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Soft Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Amorphous, Glassy
Clastic or Non-Clastic
Color
Black, Brown, Dark Brown, Grey, Light to Dark Grey
Grey, White, Yellow
Durability
Durable
Durable
Appearance
Veined or Pebbled
Soft
Interior Uses
-
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
-
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
Other Architectural Uses
-
Powder
Construction Industry
for Road Aggregate, Steel Production
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, raw material for manufacture of quicklime and slaked lime, Source of calcium
Antiquity Uses
-
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Electricity Generation
Alumina Refineries, Creating Artwork, Drawing on blackboards, Gymnasts, athletes and mountain climbers use for grip, In aquifers, Paper Industry, Production of Lime, Raw material for manufacture of quicklime, slaked lime, Soil Conditioner, Whiting, Whiting material in toothpaste, paint and paper
Types
Xyloid Lignite or Fossil Wood and Compact Lignite or Perfect Lignite
Chalk Marl and Marl
Features
Generally rough to touch, Helps in production of Heat and Electricity, Used as fossil fuel
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Archaeological Significance
Formation
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.
Chalk is formed from lime mud, which accumulates on the sea floor which is then transformed into rock by geological processes.
Mineral Content
-
Calcite, Clay, Clay Minerals, Quartz, Sand
Compound Content
Carbon, Hydrogen, Nitrogen, Oxygen, Sulphur
Ca, NaCl, CaO
Types of Metamorphism
-
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Grain Size
Medium to Fine Coarse Grained
Very fine-grained
Porosity
Highly Porous
Highly Porous
Luster
Dull to Vitreous to Submetallic
Dull
Specific Gravity
1.1-1.4
2.3-2.4
Transparency
Opaque
Opaque
Density
800-801 g/cm3
2.49-2.50 g/cm3
Resistance
Heat Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Bangladesh, Burma, Cambodia, China, India, Indonesia, Kazakhstan, Malaysia, Mongolia, Pakistan, Turkey, Vietnam
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
Africa
Botswana, Kenya, Morocco, Mozambique, South Africa, Tanzania
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Europe
Belgium, Bulgaria, England, France, Germany, Greece, Hungary, Kosovo, Netherlands, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, The Czech Republic, Ukraine, United Kingdom
England, France, Germany, Spain, United Kingdom
Deposits in Western Continents
North America
Canada, Mexico, USA
Canada, USA
South America
Brazil, Chile, Colombia, Venezuela
Colombia
Deposits in Oceania Continent
Australia
New South Wales, Queensland, Victoria
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula
All about Lignite and Chalk Properties
Know all about Lignite and Chalk properties here. All properties of rocks are important as they define the type of rock and its application. Lignite and Chalk belong to Sedimentary Rocks.Texture of Lignite is Amorphous, Glassy whereas that of Chalk is Clastic or Non-Clastic. Lignite appears Veined or Pebbled and Chalk appears Soft. The luster of Lignite is dull to vitreous to submetallic while that of Chalk is dull. Lignite is available in black, brown, dark brown, grey, light to dark grey colors whereas Chalk is available in grey, white, yellow colors. The commercial uses of Lignite are electricity generation and that of Chalk are alumina refineries, creating artwork, drawing on blackboards, gymnasts, athletes and mountain climbers use for grip, in aquifers, paper industry, production of lime, raw material for manufacture of quicklime, slaked lime, soil conditioner, whiting, whiting material in toothpaste, paint and paper.