Definition
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
Granodiorite is a coarse-grained intrusive igneous rock containing quartz and plagioclase, and which has composition in between granite and diorite
Discoverer
Unknown
Unknown
Etymology
From the locality in Essex County, Massachusetts,US
From granite + diorite
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Granular
Granular, Phaneritic
Color
Dark Grey to Black
Black, Grey, Orange, Pink, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded
Veined or Pebbled
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Bathrooms, Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Stair Treads
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, Bridges, Paving Stone, Garden Decoration, Office Buildings, Resorts
Other Architectural Uses
Curbing
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Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
As Dimension Stone
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Jewelry, Sea Defence, Tombstones
Curling, Gemstone, Laboratory bench tops, Tombstones
Types
Intermediate volcanic rock
Granodiorite
Features
Is one of the oldest rock, Smooth to touch
Available in Lots of Colors and Patterns
Archaeological Significance
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.
Granodiorite is an intrusive igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks.
Mineral Content
Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Pyroxene, Quartz
Compound Content
Aluminium Oxide, Ba, Ca, Cs, Potassium, Rb, Sodium, Sr
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering
Chemical Weathering
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Chemical Erosion, Glacier Erosion, Wind Erosion
Grain Size
Fine Grained
Medium to Coarse Grained
Porosity
Highly Porous
Less Porous
Luster
-
Grainy, Pearly and Vitreous
Specific Gravity
-9999
2.6-2.7
Transparency
Opaque
Opaque
Density
-9999 g/cm3
2.6-2.8 g/cm3
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
India, Russia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
Africa
South Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
Germany, Greece, Italy, Scotland, Turkey
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil, Colombia, Venezuela
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Deposits in Oceania Continent
Australia
New Zealand, Queensland
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