Definition
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
Gabbro is an intrusive igneous rock which is chemically equivalent to plutonic Basalt
History
Origin
USA
Germany
Discoverer
Unknown
Christian Leopold von Buch
Etymology
From the locality in Essex County, Massachusetts,US
From Latin glaber bare, smooth, bald
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Family
Group
Plutonic
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Opaque Rock
Texture
Granular
Phaneritic
Color
Dark Grey to Black
Dark Grey to Black
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Banded
Veined and Shiny
Architecture
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Countertops, Decorative Aggregates, 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, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Other Uses
Commercial Uses
Cemetery Markers, Commemorative Tablets, Jewelry, Sea Defence, Tombstones
Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Types
Intermediate volcanic rock
Anorthosite Gabbro and Norite Gabbro
Features
Is one of the oldest rock, Smooth to touch
Smooth to touch
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
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.
Gabbro, a mafic rock, forms due to cooling and crystallization of magma underneath Earth's surface.
Composition
Mineral Content
Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene
Augite, Olivine, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, Ba, Ca, Cs, Potassium, Rb, Sodium, Sr
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Impact Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering
Chemical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Coastal Erosion
Physical Properties
Hardness
77
1
7
👆🏻
Grain Size
Fine Grained
Coarse Grained
Fracture
Conchoidal
Conchoidal
Streak
Black
Black
Porosity
Highly Porous
Highly Porous
Luster
-
-
Compressive Strength
120.00 N/mm2225.00 N/mm2
0.15
450
👆🏻
Cleavage
-
-
Toughness
1.6
1.6
Specific Gravity
-99992.86-2.87
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
-9999 g/cm32.7-3.3 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.79 kJ/Kg K0.71 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
India, Russia
India, Russia
Africa
South Africa
South Africa
Europe
Germany, Greece, Italy, Scotland, Turkey
Germany, Greece, Italy, Scotland, Turkey
Others
Greenland
Greenland
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil, Colombia, Venezuela
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New Zealand, Queensland
New Zealand, Queensland