Definition
Coquina is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically-sorted fragments of the shells of molluscs, trilobites, brachiopods, or other invertebrates
Shale is a fine-grained sedimentary rock which is formed by the compaction of silt and clay-size mineral particles
Origin
European Foreland Basins
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Discoverer
Unknown
Johann Gottlob Lehmann
Etymology
From Concha (Latin)+ Coquina(Spanish) +conch(English)= Couquina (mid 19th century)
From German Schalstein laminated limestone, and Schalgebirge layer of stone in stratified rock. From Old English scealu in its base sense of- thing that divides or separate,
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic
Clastic, Splintery
Color
Beige, Buff, Orange
Black, Brown, Buff, Green, Grey, Red, Yellow
Durability
Non-Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Muddy
Interior Uses
Decorative Aggregates, Homes, Hotels, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
Building houses or walls, Construction Aggregate
Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Sculpture
Commercial Uses
Creating Artwork
Creating Artwork, Pottery
Types
Sedimentary rock
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Features
Available in Lots of Colors and Patterns, Is one of the oldest rock
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Archaeological Significance
Famous Monuments
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Jantar Mantar in India
Formation
Coquina is a sedimentary rock which is formed when billions of small clam-like seashell, called Coquina, or cockleshell are die and hence are deposited, buried and turns into a rock when pressure is applied.
Shale forms when very fine-grained clay particles are deposited in water which settle at the bottom of water bodies. They are later compacted hence forming shale.
Mineral Content
Apatite, Augite, Bronzite, Calcite, Chert, Chlorite, Clay Minerals, Epidote, Feldspar, Garnet, Micas, Muscovite or Illite
Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides
Compound Content
CaO, Carbon Dioxide, Iron(III) Oxide, MgO
Ca, Fe, Mg, Silicon Dioxide, Sodium
Types of Metamorphism
-
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Coarse Grained
Very fine-grained
Porosity
Highly Porous
Highly Porous
Luster
Dull to Vitreous to Submetallic
Dull
Specific Gravity
1.10-2.24
2.2-2.8
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
2.4-2.8 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
-
Bangladesh, China, India, Russia
Africa
-
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
United Kingdom
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Deposits in Western Continents
South America
-
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
-
New South Wales, New Zealand, Queensland, Victoria, Western Australia
Coquina vs Shale 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. Coquina vs Shale characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Coquina and Properties of Shale. Learn more about Coquina vs Shale in the next section. The interior uses of Coquina include Decorative aggregates, Homes, Hotels and Interior decoration whereas the interior uses of Shale include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Coquina and Shale, they have various applications in construction industry. The uses of Coquina in construction industry include Building houses or walls, Construction aggregate and that of Shale include Cement manufacture, Construction aggregate, For road aggregate, Making natural cement, Raw material for the manufacture of mortar.
More about Coquina and Shale
Here you can know more about Coquina and Shale. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Coquina and Shale consists of mineral content and compound content. The mineral content of Coquina includes Apatite, Augite, Bronzite, Calcite, Chert, Chlorite, Clay Minerals, Epidote, Feldspar, Garnet, Micas, Muscovite or Illite and mineral content of Shale includes Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides. You can also check out the list of all Sedimentary Rocks. When we have to compare Coquina vs Shale, the texture, color and appearance plays an important role in determining the type of rock. Coquina is available in beige, buff, orange colors whereas, Shale is available in black, brown, buff, green, grey, red, yellow colors. Appearance of Coquina is Layered, Banded, Veined and Shiny and that of Shale is Muddy. Properties of rock is another aspect for Coquina vs Shale. The hardness of Coquina is 1-2 and that of Shale is 3. The types of Coquina are Sedimentary rock whereas types of Shale are Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Coquina and Shale is white. The specific heat capacity of Coquina is 0.84 kJ/Kg K and that of Shale is 0.39 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Coquina is heat resistant, impact resistant, pressure resistant, wear resistant whereas Shale is heat resistant, impact resistant.