1 Definition
1.1 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
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
1.2 History
1.2.1 Origin
European Foreland Basins
Romania and Moldova, Europe
1.2.2 Discoverer
1.3 Etymology
From Concha (Latin)+ Coquina(Spanish) +conch(English)= Couquina (mid 19th century)
From Dacia, a province of the Roman Empire which lay between the Danube River and Carpathian Mountains where the rock was first described
1.4 Class
Sedimentary Rocks
Igneous Rocks
1.4.1 Sub-Class
Durable Rock, Soft Rock
Durable Rock, Soft Rock
1.5 Family
1.5.1 Group
1.6 Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
2 Texture
2.1 Texture
Clastic
Aphanitic to Porphyritic
2.2 Color
Beige, Buff, Orange
Bluish - Grey, Brown, Grey, Light to Dark Grey
2.3 Maintenance
2.4 Durability
2.4.1 Water Resistant
2.4.2 Scratch Resistant
2.4.3 Stain Resistant
2.4.4 Wind Resistant
2.4.5 Acid Resistant
2.5 Appearance
Layered, Banded, Veined and Shiny
Vesicular
3 Uses
3.1 Architecture
3.1.1 Interior Uses
Decorative Aggregates, Homes, Hotels, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
3.1.2 Exterior Uses
Garden Decoration, Office Buildings
As Building Stone, Paving Stone, Garden Decoration
3.1.3 Other Architectural Uses
3.2 Industry
3.2.1 Construction Industry
Building houses or walls, Construction Aggregate
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
3.2.2 Medical Industry
Not Yet Used
Not Yet Used
3.3 Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
3.4 Other Uses
3.4.1 Commercial Uses
Creating Artwork
Commemorative Tablets, Creating Artwork
4 Types
4.1 Types
Not Available
Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite
4.2 Features
Available in Lots of Colors and Patterns, Is one of the oldest rock
Host Rock for Lead, Is one of the oldest rock
4.3 Archaeological Significance
4.3.1 Monuments
4.3.2 Famous Monuments
Data Not Available
Not Applicable
4.3.3 Sculpture
4.3.4 Famous Sculptures
Data Not Available
Not Applicable
4.3.5 Pictographs
4.3.6 Petroglyphs
4.3.7 Figurines
4.4 Fossils
5 Formation
5.1 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.
Dacitic magma is formed by the subduction of young oceanic crust under a thick felsic continental plate. Further, the Oceanic crust is hydrothermally altered as quartz and sodium are added.
5.2 Composition
5.2.1 Mineral Content
Apatite, Augite, Bronzite, Calcite, Chert, Chlorite, Clay Minerals, Epidote, Feldspar, Garnet, Micas, Muscovite or Illite
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
5.2.2 Compound Content
CaO, Carbon Dioxide, Iron(III) Oxide, MgO
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide
5.3 Transformation
5.3.1 Metamorphism
5.3.2 Types of Metamorphism
Not Applicable
Burial Metamorphism, Cataclastic Metamorphism
5.3.3 Weathering
5.3.4 Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
5.3.5 Erosion
5.3.6 Types of Erosion
Coastal Erosion, Sea Erosion, Water Erosion, Wind Erosion
Chemical Erosion
6 Properties
6.1 Physical Properties
6.1.1 Hardness
6.1.2 Grain Size
Coarse Grained
Medium to Fine Coarse Grained
6.1.3 Fracture
6.1.4 Streak
6.1.5 Porosity
Highly Porous
Less Porous
6.1.6 Luster
Dull to Vitreous to Submetallic
Subvitreous to Dull
6.1.7 Compressive Strength
6.1.8 Cleavage
6.1.9 Toughness
Not Available
Not Available
6.1.10 Specific Gravity
6.1.11 Transparency
6.1.12 Density
2.8-2.9 g/cm32.77-2.771 g/cm3
0
1400
6.2 Thermal Properties
6.2.1 Specific Heat Capacity
6.2.2 Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
7 Reserves
7.1 Deposits in Eastern Continents
7.1.1 Asia
Not Yet Found
Not Yet Found
7.1.2 Africa
Not Yet Found
Not Yet Found
7.1.3 Europe
United Kingdom
France, Greece, Romania, Scotland, Spain
7.1.4 Others
Not Yet Found
Not Yet Found
7.2 Deposits in Western Continents
7.2.1 North America
7.2.2 South America
Not Yet Found
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
7.3 Deposits in Oceania Continent
7.3.1 Australia
Not Yet Found
New Zealand, South Australia, Western Australia