Definition
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Theralite is a plutonic hylocrystalline igneous rock consisting of augite, olivine, calcic plagioclase and nepheline
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 Greek to pursue
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Group
Not Applicable
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic or Non-Clastic
Phaneritic
Color
Grey, White, Yellow
Dark Grey to Black
Durability
Durable
Durable
Appearance
Soft
Veined and Shiny
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Powder
Curbing
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
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
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
Cemetery Markers, Commemorative Tablets, Creating Artwork, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Types
Not Available
Teschenite and Essexite
Features
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Smooth to touch
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Formation
Chalk is formed from lime mud, which accumulates on the sea floor which is then transformed into rock by geological processes.
Theralite 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
Calcite, Clay, Clay Minerals, Quartz, Sand
Augite, Olivine, Plagioclase, Pyroxene
Compound Content
Ca, NaCl, CaO
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Types of Metamorphism
Not Applicable
Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Fine Grained
Fracture
Not Available
Uneven, Splintery or Conchoidal
Porosity
Highly Porous
Highly Porous
Luster
Dull
Waxy and Dull
Cleavage
Non-Existent
Non-Existent
Specific Gravity
2.3-2.4
2.5-2.8
Transparency
Opaque
Translucent to Opaque
Density
2.49-2.50 g/cm3
2.7 g/cm3
Resistance
Heat Resistant
Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
India, Russia
Africa
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
South Africa
Europe
England, France, Germany, Spain, United Kingdom
Germany, Greece, Italy, Scotland, Turkey
Others
Not Yet Found
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Colombia
Bolivia, Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
Adelaide, New Zealand, Queensland, Tonga, Victoria, Yorke Peninsula
New Zealand, Queensland
All about Chalk and Theralite Properties
Know all about Chalk and Theralite properties here. All properties of rocks are important as they define the type of rock and its application. Chalk belongs to Sedimentary Rocks while Theralite belongs to Igneous Rocks.Texture of Chalk is Clastic or Non-Clastic whereas that of Theralite is Phaneritic. Chalk appears Soft and Theralite appears Veined and Shiny. The luster of Chalk is dull while that of Theralite is waxy and dull. Chalk is available in grey, white, yellow colors whereas Theralite is available in dark grey to black colors. The commercial uses 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 and that of Theralite are cemetery markers, commemorative tablets, creating artwork, laboratory bench tops, jewelry, sea defence, tombstones.