Definition
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
Tephrite is an aphanitic to porphyritic textured, volcanic igneous rock
Discoverer
Unknown
Van Tooren
Etymology
From the locality in Essex County, Massachusetts,US
From Greek tephra, ashes from Indo-European base, to burn
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Granular
Aphanitic to Porphyritic
Color
Dark Grey to Black
Black, Brown, Colourless, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded
Vesicular
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Landscaping
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Jewelry, Sea Defence, Tombstones
Production of Lime, Soil Conditioner
Types
Not Available
Not Available
Features
Is one of the oldest rock, Smooth to touch
Host Rock for Lead
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Formation
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.
Tephrite 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.
Mineral Content
Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene
Alkali feldspar, Nepheline, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, Ba, Ca, Cs, Potassium, Rb, Sodium, Sr
CaO, Carbon Dioxide, MgO, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
Conchoidal
Uneven
Streak
Black
Bluish Black
Porosity
Highly Porous
Very Less Porous
Luster
Not Available
Subvitreous to Dull
Compressive Strength
Not Available
Cleavage
Not Available
Crenulation and Pervasive
Specific Gravity
Not Available
2.86
Transparency
Opaque
Opaque
Density
Not Available
2.8-2.9 g/cm3
Specific Heat Capacity
Not Available
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
India, Russia
Not Yet Found
Africa
South Africa
Namibia, Uganda
Europe
Germany, Greece, Italy, Scotland, Turkey
Germany, Hungary, Italy, Portugal, Spain
Others
Greenland
Not Yet Found
Deposits in Western Continents
North America
Canada, USA
USA
South America
Brazil, Colombia, Venezuela
Not Yet Found
Deposits in Oceania Continent
Australia
New Zealand, Queensland
New Zealand, Western Australia
Essexite vs Tephrite 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. Essexite vs Tephrite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Essexite and Properties of Tephrite. Learn more about Essexite vs Tephrite in the next section. The interior uses of Essexite include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Tephrite include Decorative aggregates, Flooring, Homes and Interior decoration. Due to some exceptional properties of Essexite and Tephrite, they have various applications in construction industry. The uses of Essexite in construction industry include As dimension stone, Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate and that of Tephrite include Landscaping.
More about Essexite and Tephrite
Here you can know more about Essexite and Tephrite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Essexite and Tephrite consists of mineral content and compound content. The mineral content of Essexite includes Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene and mineral content of Tephrite includes Alkali feldspar, Nepheline, Plagioclase, Pyroxene. You can also check out the list of all Igneous Rocks. When we have to compare Essexite vs Tephrite, the texture, color and appearance plays an important role in determining the type of rock. Essexite is available in dark grey to black colors whereas, Tephrite is available in black, brown, colourless, green, grey, white colors. Appearance of Essexite is Banded and that of Tephrite is Vesicular. Properties of rock is another aspect for Essexite vs Tephrite. The hardness of Essexite is 7 and that of Tephrite is 6.5. The types of Essexite are Not Available whereas types of Tephrite are Not Available. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Essexite is black while that of Tephrite is bluish black. The specific heat capacity of Essexite is Not Available and that of Tephrite is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Essexite is impact resistant, pressure resistant, wear resistant whereas Tephrite is heat resistant, impact resistant.