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
Talc carbonate is nothing but a rock sequence or a mineral composition found in metamorphic ultramafic rocks.
Origin
European Foreland Basins
China, USA, Middle east
Discoverer
Unknown
Unknown
Etymology
From Concha (Latin)+ Coquina(Spanish) +conch(English)= Couquina (mid 19th century)
From medieval Latin, talcum
Class
Sedimentary Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Soft Rock
Group
Not Applicable
Not Applicable
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic
Very Soft
Color
Beige, Buff, Orange
Colourless, Grey, White
Durability
Non-Durable
Durable
Appearance
Layered, Banded, Veined and Shiny
Soft
Interior Uses
Decorative Aggregates, Homes, Hotels, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
Garden Decoration, Office Buildings
Garden Decoration
Other Architectural Uses
Curbing
Powder
Construction Industry
Building houses or walls, Construction Aggregate
Source of calcium
Medical Industry
Not Yet Used
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Jewellery, Monuments, Sculpture, Small Figurines
Commercial Uses
Creating Artwork
Manufacturing of baby powder
Types
Not Available
Not Available
Features
Available in Lots of Colors and Patterns, Is one of the oldest rock
Easily splits into thin plates, Generally rough to touch, Host Rock for Lead
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Petroglyphs
Used
Not Used
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.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Talc Carbonate is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Apatite, Augite, Bronzite, Calcite, Chert, Chlorite, Clay Minerals, Epidote, Feldspar, Garnet, Micas, Muscovite or Illite
Carbonate, Chlorite, Magnesium
Compound Content
CaO, Carbon Dioxide, Iron(III) Oxide, MgO
CaO, Carbon Dioxide, MgO
Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Not Applicable
Types of Erosion
Coastal Erosion, Sea Erosion, Water Erosion, Wind Erosion
Not Applicable
Grain Size
Coarse Grained
Fine Grained
Porosity
Highly Porous
Less Porous
Luster
Dull to Vitreous to Submetallic
Pearly
Compressive Strength
Not Available
Cleavage
Not Available
Perfect
Toughness
Not Available
1
Specific Gravity
1.10-2.24
2.86
Transparency
Opaque
Translucent
Density
2.8-2.9 g/cm3
2.8-2.9 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
Not Yet Found
Africa
Not Yet Found
Ethiopia, Ghana, Western Africa
Europe
United Kingdom
England
Others
Not Yet Found
Not Yet Found
Deposits in Western Continents
North America
USA
Canada, USA
South America
Not Yet Found
Argentina, Bolivia, Uruguay
Deposits in Oceania Continent
Australia
Not Yet Found
Central Australia, South Australia, Western Australia