Definition
Blueschist is a metamorphic rock which is generally blue in color and is formed under conditions of high pressure and low temperature
Chalk is a soft, white, powdery limestone consisting mainly of fossil shells of foraminifers
Discoverer
Edgar Bailey
Unknown
Etymology
From French schiste, Greek skhistos i.e. split
From old English cealc chalk, lime, plaster; pebble, from Greek khalix small pebble, in English transferred to the opaque, white, soft limestone
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated
Clastic or Non-Clastic
Color
Blue, Bluish - Grey, Purple, Shades of Blue
Grey, White, Yellow
Durability
Durable
Durable
Appearance
Dull and Banded
Soft
Interior Uses
Floor Tiles, Flooring, Homes, Hotels, Kitchens
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration
Other Architectural Uses
-
Powder
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
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
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Curling, Tombstones
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
Metamorphic rock
Chalk Marl and Marl
Features
Has High structural resistance against erosion and climate, Very fine grained rock
Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Archaeological Significance
Formation
Blueschist forms due to the metamorphism of basalt and other rocks with similar composition at high pressures and low temperatures and approximately corresponding to a depth of 15 to 30 kilometers and 200 to 500 °C.
Chalk is formed from lime mud, which accumulates on the sea floor which is then transformed into rock by geological processes.
Mineral Content
Albite, Chlorite, Epidote, Garnet, Glaucophane, Lawsonite, Muscovite or Illite, Quartz
Calcite, Clay, Clay Minerals, Quartz, Sand
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Ca, NaCl, CaO
Types of Metamorphism
-
-
Types of Weathering
Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Grain Size
Fine to Medium Grained
Very fine-grained
Streak
White to Grey
White
Porosity
Highly Porous
Highly Porous
Specific Gravity
3-3.2
2.3-2.4
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
2.49-2.50 g/cm3
Resistance
Impact Resistant, Pressure Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
Japan, Turkey
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
Africa
Egypt, Ethiopia, South Africa
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Europe
France, Greece, Iceland
England, France, Germany, Spain, United Kingdom
Deposits in Western Continents
North America
USA
Canada, USA
Deposits in Oceania Continent
Australia
New Zealand
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula
Blueschist vs Chalk 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. Blueschist vs Chalk characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Blueschist and Properties of Chalk. Learn more about Blueschist vs Chalk in the next section. The interior uses of Blueschist include Floor tiles, Flooring, Homes, Hotels and Kitchens whereas the interior uses of Chalk include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Blueschist and Chalk, they have various applications in construction industry. The uses of Blueschist in construction industry include As dimension stone, Cobblestones, Rail track ballast, Roadstone and that of Chalk 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.
More about Blueschist and Chalk
Here you can know more about Blueschist and Chalk. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Blueschist and Chalk consists of mineral content and compound content. The mineral content of Blueschist includes Albite, Chlorite, Epidote, Garnet, Glaucophane, Lawsonite, Muscovite or Illite, Quartz and mineral content of Chalk includes Calcite, Clay, Clay Minerals, Quartz, Sand. You can also check out the list of all Igneous Rocks. When we have to compare Blueschist vs Chalk, the texture, color and appearance plays an important role in determining the type of rock. Blueschist is available in blue, bluish - grey, purple, shades of blue colors whereas, Chalk is available in grey, white, yellow colors. Appearance of Blueschist is Dull and Banded and that of Chalk is Soft. Properties of rock is another aspect for Blueschist vs Chalk. The hardness of Blueschist is 3.5-4 and that of Chalk is 1. The types of Blueschist are Metamorphic rock whereas types of Chalk are Chalk Marl and Marl. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Blueschist is white to grey while that of Chalk is white. The specific heat capacity of Blueschist is 0.84 kJ/Kg K and that of Chalk is 0.90 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Blueschist is impact resistant, pressure resistant whereas Chalk is heat resistant.