Definition
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Basanite is a black basaltic rock which mainly contains plagioclase, augite, olivine and nepheline and is formerly used as a touchstone
History
Origin
-
-
Discoverer
Unknown
Unknown
Etymology
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
From Latin basanites + -ite
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic or Non-Clastic
Aphanitic to Porphyritic
Color
Grey, White, Yellow
Black, Brown, Green, Grey, Red, White
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Soft
Glassy or Pearly
Architecture
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Homes
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
As Building Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Powder
Whetstones
Industry
Construction Industry
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
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments
Other Uses
Commercial Uses
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
As a touchstone, Creating Artwork, Gemstone, In fire-starting tools, Manufacture of tools, Metallurgical Flux, Jewelry, To ignite fire, Used in flintlock firearms
Types
Chalk Marl and Marl
Nepheline-Basanite, Analcite-Basanite and Leucite-Basanite
Features
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate, Used as a touchstone
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Present
Absent
Formation
Chalk is formed from lime mud, which accumulates on the sea floor which is then transformed into rock by geological processes.
Basanite is a fine-grained, hard rock that forms when bits of lava shoot out of volcanoes.
Composition
Mineral Content
Calcite, Clay, Clay Minerals, Quartz, Sand
Augite, Feldspar, Ilmenite, Olivine, Plagioclase
Compound Content
Ca, NaCl, CaO
Potassium Oxide, Sodium Oxide, Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering
Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
17
1
7
👆🏻
Grain Size
Very fine-grained
Fine Grained
Fracture
-
Uneven, Splintery or Conchoidal
Streak
White
White
Porosity
Highly Porous
Highly Porous
Luster
Dull
Waxy and Dull
Compressive Strength
5.00 N/mm2100.00 N/mm2
0.15
450
👆🏻
Cleavage
-
-
Toughness
1
1.5
Specific Gravity
2.3-2.42.5-2.8
0
8.4
👆🏻
Transparency
Opaque
Translucent to Opaque
Density
2.49-2.50 g/cm32.7 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.90 kJ/Kg K0.74 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
-
Africa
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Uganda
Europe
England, France, Germany, Spain, United Kingdom
Germany, Hungary, Italy, Spain
Others
-
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Canada, USA
USA
South America
Colombia
Bolivia, Brazil
Deposits in Oceania Continent
Australia
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula
New South Wales, New Zealand, Queensland, South Australia, Western Australia