Definition
Dacite is a volcanic igneous rock which is rintermediate in composition between andesite and rhyolite
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
Origin
Romania and Moldova, Europe
USA
Discoverer
Unknown
Unknown
Etymology
From Dacia, a province of the Roman Empire which lay between the Danube River and Carpathian Mountains where the rock was first described
From the locality in Essex County, Massachusetts,US
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Aphanitic to Porphyritic
Granular
Color
Bluish - Grey, Brown, Grey, Light to Dark Grey
Dark Grey to Black
Durability
Durable
Durable
Appearance
Vesicular
Banded
Interior Uses
Decorative Aggregates, Entryways, Interior Decoration
Decorative Aggregates, Homes, Interior Decoration
Exterior Uses
As Building Stone, Paving Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Construction Aggregate, for Road Aggregate, Landscaping
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Commemorative Tablets, Creating Artwork
Cemetery Markers, Commemorative Tablets, Jewelry, Sea Defence, Tombstones
Types
Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite
Not Available
Features
Host Rock for Lead, Is one of the oldest rock
Is one of the oldest rock, Smooth to touch
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Sculpture
Not Yet Used
Used
Famous Sculptures
Not Applicable
Data Not Available
Pictographs
Used
Not Used
Petroglyphs
Used
Not Used
Figurines
Not Yet Used
Used
Formation
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.
Essexite is a type of igneous rock, which is usually dark grey to black plutonic rock. For the formation of essexite, suitable magma with exact composition of K, Ba, Rb, Cs, Sr should be produced.
Mineral Content
Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon
Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene
Compound Content
Ca, Fe, Potassium Oxide, Mg, Potassium, Silicon Dioxide
Aluminium Oxide, Ba, Ca, Cs, Potassium, Rb, Sodium, Sr
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Conchoidal
Conchoidal
Porosity
Less Porous
Highly Porous
Luster
Subvitreous to Dull
Not Available
Cleavage
Perfect
Not Available
Toughness
Not Available
1.6
Specific Gravity
2.86-2.87
Not Available
Transparency
Translucent
Opaque
Density
2.77-2.771 g/cm3
Not Available
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Not Yet Found
India, Russia
Africa
Not Yet Found
South Africa
Europe
France, Greece, Romania, Scotland, Spain
Germany, Greece, Italy, Scotland, Turkey
Others
Not Yet Found
Greenland
Deposits in Western Continents
North America
USA
Canada, USA
South America
Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New Zealand, South Australia, Western Australia
New Zealand, Queensland
Dacite vs Essexite 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. Dacite vs Essexite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Dacite and Properties of Essexite . Learn more about Dacite vs Essexite in the next section. The interior uses of Dacite include Decorative aggregates, Entryways and Interior decoration whereas the interior uses of Essexite include Decorative aggregates, Homes and Interior decoration. Due to some exceptional properties of Dacite and Essexite , they have various applications in construction industry. The uses of Dacite in construction industry include As dimension stone, Construction aggregate, For road aggregate, Landscaping and that of Essexite include As dimension stone, Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate.
More about Dacite and Essexite
Here you can know more about Dacite and Essexite . The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Dacite and Essexite consists of mineral content and compound content. The mineral content of Dacite includes Amphibole, Apatite, Biotite, Feldspar, Garnet, Hornblade, Magnetite, Plagioclase, Pyroxene, Quartz, Zircon and mineral content of Essexite includes Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene. You can also check out the list of all Igneous Rocks. When we have to compare Dacite vs Essexite , the texture, color and appearance plays an important role in determining the type of rock. Dacite is available in bluish - grey, brown, grey, light to dark grey colors whereas, Essexite is available in dark grey to black colors. Appearance of Dacite is Vesicular and that of Essexite is Banded. Properties of rock is another aspect for Dacite vs Essexite . The hardness of Dacite is 2-2.25 and that of Essexite is 7. The types of Dacite are Footwall Dacite, Hanging wall Dacite, Tuff and Biotite Dacite whereas types of Essexite are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Dacite is white while that of Essexite is black. The specific heat capacity of Dacite is 0.92 kJ/Kg K and that of Essexite is Not Available. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Dacite is heat resistant, impact resistant, pressure resistant, wear resistant whereas Essexite is impact resistant, pressure resistant, wear resistant.