Definition
Nephelinite is a fine-grained or aphanitic igneous rock made up almost entirely of nepheline and clinopyroxene (variety augite).
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
Origin
Brazil
European Foreland Basins
Discoverer
Unknown
Unknown
Etymology
from French néphéline, from Greek nephelē
From Concha (Latin)+ Coquina(Spanish) +conch(English)= Couquina (mid 19th century)
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Soft Rock
Group
Plutonic
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Aphanitic
Clastic
Color
Black, Brown, Colourless, Green, Grey, White
Beige, Buff, Orange
Durability
Durable
Non-Durable
Appearance
Skeletal
Layered, Banded, Veined and Shiny
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Homes, Hotels, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate
Building houses or walls, Construction Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork, Soil Conditioner, Source of Magnesia (MgO)
Creating Artwork
Types
Peralkaline Nephelinite
Not Available
Features
Host Rock for Lead
Available in Lots of Colors and Patterns, Is one of the oldest rock
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Formation
Nephelinite 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.
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.
Mineral Content
Clinopyroxene, Nepheline, Plagioclase
Apatite, Augite, Bronzite, Calcite, Chert, Chlorite, Clay Minerals, Epidote, Feldspar, Garnet, Micas, Muscovite or Illite
Compound Content
Ca, CaO, Carbon, Cl, MgO
CaO, Carbon Dioxide, Iron(III) Oxide, MgO
Types of Metamorphism
Contact Metamorphism
Not Applicable
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Coastal Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Coarse Grained
Porosity
Less Porous
Highly Porous
Luster
Vitreous to Metallic
Dull to Vitreous to Submetallic
Compressive Strength
Not Available
Cleavage
Imperfect
Not Available
Toughness
2.7
Not Available
Specific Gravity
2.4-2.9
1.10-2.24
Transparency
Opaque
Opaque
Density
2.5-3 g/cm3
2.8-2.9 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Africa
Rwanda, Tanzania
Not Yet Found
Europe
Not Yet Found
United Kingdom
Others
Hawaii Islands
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
USA
South America
Colombia
Not Yet Found
Deposits in Oceania Continent
Australia
Not Yet Found
Not Yet Found
Nephelinite vs Coquina 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. Nephelinite vs Coquina characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Nephelinite and Properties of Coquina. Learn more about Nephelinite vs Coquina in the next section. The interior uses of Nephelinite include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Coquina include Decorative aggregates, Homes, Hotels and Interior decoration. Due to some exceptional properties of Nephelinite and Coquina, they have various applications in construction industry. The uses of Nephelinite in construction industry include As dimension stone, Cement manufacture, Construction aggregate, For road aggregate and that of Coquina include Building houses or walls, Construction aggregate.
More about Nephelinite and Coquina
Here you can know more about Nephelinite and Coquina. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Nephelinite and Coquina consists of mineral content and compound content. The mineral content of Nephelinite includes Clinopyroxene, Nepheline, Plagioclase and mineral content of Coquina includes Apatite, Augite, Bronzite, Calcite, Chert, Chlorite, Clay Minerals, Epidote, Feldspar, Garnet, Micas, Muscovite or Illite. You can also check out the list of all . When we have to compare Nephelinite vs Coquina, the texture, color and appearance plays an important role in determining the type of rock. Nephelinite is available in black, brown, colourless, green, grey, white colors whereas, Coquina is available in beige, buff, orange colors. Appearance of Nephelinite is Skeletal and that of Coquina is Layered, Banded, Veined and Shiny. Properties of rock is another aspect for Nephelinite vs Coquina. The hardness of Nephelinite is 6.5 and that of Coquina is 1-2. The types of Nephelinite are Peralkaline Nephelinite whereas types of Coquina are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Nephelinite and Coquina is white. The specific heat capacity of Nephelinite is 0.88 kJ/Kg K and that of Coquina is Not Available. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Nephelinite is heat resistant whereas Coquina is heat resistant, impact resistant, pressure resistant, wear resistant.
