Definition
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
  
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
  
History
  
  
Origin
USA
  
Italy
  
Discoverer
Unknown
  
Unknown
  
Etymology
From the locality in Essex County, Massachusetts,US
  
Comendite derives its name from the area of Le Commende on San Pietro Island in Italy
  
Class
Igneous Rocks
  
Igneous Rocks
  
Sub-Class
Durable Rock, Hard Rock
  
Durable Rock, Hard Rock
  
Family
  
  
Group
Plutonic
  
Volcanic
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Medium Grained Rock, Opaque Rock
  
Texture
Granular
  
Porphyritic
  
Color
Dark Grey to Black
  
Blue, Bluish - Grey
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
Yes
  
Yes
  
Wind Resistant
Yes
  
Yes
  
Acid Resistant
No
  
Yes
  
Appearance
Banded
  
Foliated
  
Architecture
  
  
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
  
Countertops, Decorative Aggregates, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
  
As Building Stone, As Facing Stone, Garden Decoration
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
  
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar
  
Medical Industry
Not Yet Used
  
Not Yet Used
  
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
  
Artifacts
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Commemorative Tablets, Jewelry, Sea Defence, Tombstones
  
Cemetery Markers
  
Types
Not Available
  
Rhyolite
  
Features
Is one of the oldest rock, Smooth to touch
  
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
  
Archaeological Significance
  
  
Monuments
Used
  
Not Yet Used
  
Famous Monuments
Data Not Available
  
Not Applicable
  
Sculpture
Used
  
Not Yet Used
  
Famous Sculptures
Data Not Available
  
Not Applicable
  
Pictographs
Not Used
  
Not Used
  
Petroglyphs
Not Used
  
Not Used
  
Figurines
Used
  
Not Yet Used
  
Fossils
Absent
  
Absent
  
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.
  
Comendite is a type of Igneous rock which is formed due to cooling and solidification of lava or magma. It may form with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
  
Composition
  
  
Mineral Content
Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene
  
Albite, Amphibole, Quartz
  
Compound Content
Aluminium Oxide, Ba, Ca, Cs, Potassium, Rb, Sodium, Sr
  
Al, Fe, Potassium Oxide
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
  
Cataclastic Metamorphism, Regional Metamorphism
  
Weathering
Yes
  
Yes
  
Types of Weathering
Biological Weathering, Chemical Weathering
  
Biological Weathering, Chemical Weathering, Mechanical Weathering
  
Erosion
Yes
  
Yes
  
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
  
Coastal Erosion, Water Erosion
  
Physical Properties
  
  
Hardness
7
  
6-7
  
Grain Size
Fine Grained
  
Medium Grained
  
Fracture
Conchoidal
  
Pervasive
  
Streak
Black
  
Bluish Black
  
Porosity
Highly Porous
  
Highly Porous
  
Luster
Not Available
  
Dull
  
Compressive Strength
Not Available
  
92.40 N/mm
2
  
21
Cleavage
Not Available
  
Not Available
  
Toughness
1.6
  
2
  
Specific Gravity
Not Available
  
2.38
  
Transparency
Opaque
  
Opaque
  
Density
Not Available
  
Not Available
  
Thermal Properties
  
  
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
  
Heat Resistant, Impact Resistant
  
Deposits in Eastern Continents
  
  
Asia
India, Russia
  
China
  
Africa
South Africa
  
East Africa
  
Europe
Germany, Greece, Italy, Scotland, Turkey
  
Italy
  
Others
Greenland
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
Not Yet Found
  
South America
Brazil, Colombia, Venezuela
  
Not Yet Found
  
Deposits in Oceania Continent
  
  
Australia
New Zealand, Queensland
  
Queensland
  
Essexite vs Comendite 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 Comendite characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Essexite and Properties of Comendite. Learn more about Essexite vs Comendite in the next section. The interior uses of Essexite include Decorative aggregates, Homes and Interior decoration whereas the interior uses of Comendite include Countertops, Decorative aggregates and Interior decoration. Due to some exceptional properties of Essexite and Comendite, 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 Comendite include Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate, Landscaping, Making natural cement, Raw material for the manufacture of mortar.
More about Essexite and Comendite
Here you can know more about Essexite and Comendite. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Essexite and Comendite consists of mineral content and compound content. The mineral content of Essexite includes Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene and mineral content of Comendite includes Albite, Amphibole, Quartz. You can also check out the list of all Igneous Rocks. When we have to compare Essexite vs Comendite, 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, Comendite is available in blue, bluish - grey colors. Appearance of Essexite is Banded and that of Comendite is Foliated. Properties of rock is another aspect for Essexite vs Comendite. The hardness of Essexite is 7 and that of Comendite is 6-7. The types of Essexite are Not Available whereas types of Comendite are Rhyolite. 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 Comendite is bluish black. The specific heat capacity of Essexite is Not Available and that of Comendite is Not Available. 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 Comendite is heat resistant, impact resistant.