Definition
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Greywacke is defined as a dark coarse-grained sandstone rock which contains more than 15 per cent clay
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 German Grauwacke, from grau grey + wacke
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Group
Not Applicable
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic or Non-Clastic
Clastic
Color
Grey, White, Yellow
Beige, Black, Brown, Colourless, Cream, Dark Brown, Green, Grey, Light Green, Light to Dark Grey, Pink, Red, White, Yellow
Durability
Durable
Durable
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Floor Tiles, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Powder
Curbing, Whetstones
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
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Sculpture, Small Figurines
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 armour rock for sea walls, Petroleum reservoirs, Sea Defence, Tombstones
Types
Not Available
Not Available
Features
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Available in Lots of Colors and Patterns, Generally rough to touch, Non-vesicular, Veined
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
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.
Graywacke rock is a type of sedimentary rock, which is also known as immature sandstone, which is indurated, dark grey and consisting of poorly sorted angular to sub-angular, sand-sized grains.
Mineral Content
Calcite, Clay, Clay Minerals, Quartz, Sand
Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Ca, NaCl, CaO
Aluminium Oxide, NaCl, CaO, Chromium(III) Oxide, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Not Applicable
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Coastal Erosion, Sea Erosion, Wind Erosion
Grain Size
Very fine-grained
Angular and Fine
Fracture
Not Available
Conchoidal
Porosity
Highly Porous
Highly Porous
Cleavage
Non-Existent
Perfect
Specific Gravity
2.3-2.4
2.2-2.8
Transparency
Opaque
Opaque
Density
2.49-2.50 g/cm3
2.6-2.61 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
Africa
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Namibia, Nigeria, South Africa
Europe
England, France, Germany, Spain, United Kingdom
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Others
Not Yet Found
Greenland
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Colombia
Brazil
Deposits in Oceania Continent
Australia
Adelaide, New Zealand, Queensland, Tonga, Victoria, Yorke Peninsula
New South Wales, New Zealand
Chalk vs Greywacke Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Chalk vs Greywacke characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Chalk and Properties of Greywacke. Learn more about Chalk vs Greywacke in the next section. The interior uses of Chalk include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Greywacke include Decorative aggregates, Floor tiles, Flooring, Homes and Interior decoration. Due to some exceptional properties of Chalk and Greywacke, they have various applications in construction industry. The uses of Chalk in construction industry include 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 and that of Greywacke include Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate, Raw material for the manufacture of mortar.
More about Chalk and Greywacke
Here you can know more about Chalk and Greywacke. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Chalk and Greywacke consists of mineral content and compound content. The mineral content of Chalk includes Calcite, Clay, Clay Minerals, Quartz, Sand and mineral content of Greywacke includes Augite, Biotite, Calcite, Chlorite, Clay, Clay Minerals, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz. You can also check out the list of all Sedimentary Rocks. When we have to compare Chalk vs Greywacke, the texture, color and appearance plays an important role in determining the type of rock. Chalk is available in grey, white, yellow colors whereas, Greywacke is available in beige, black, brown, colourless, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors. Appearance of Chalk is Soft and that of Greywacke is Dull. Properties of rock is another aspect for Chalk vs Greywacke. The hardness of Chalk is 1 and that of Greywacke is 6-7. The types of Chalk are Not Available whereas types of Greywacke are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Chalk and Greywacke is white. The specific heat capacity of Chalk is 0.90 kJ/Kg K and that of Greywacke is Not Available. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Chalk is heat resistant whereas Greywacke is heat resistant, impact resistant, pressure resistant.