Definition
Essexite which is also known as nepheline monzogabbro, is a dark gray or black holocrystalline plutonic Iigneous Rock
Hawaiite is volcanic rock that resembles basalt. It is an olivine basalt with intermediate composition between alkali olivine and mugearite
Origin
USA
Hawaii Islands
Discoverer
Unknown
Joseph Iddings
Etymology
From the locality in Essex County, Massachusetts,US
From Hawaii Islands
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Opaque Rock
Texture
Granular
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Color
Dark Grey to Black
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded
Dull and Soft
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Paving 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
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Jewelry, Sea Defence, Tombstones
Creating Artwork, Sea Defence
Types
Not Available
Not Available
Features
Is one of the oldest rock, Smooth to touch
Has High structural resistance against erosion and climate, Very fine grained rock
Archaeological Significance
Famous Monuments
Data Not Available
Easter Island in the Polynesian Triangle, Pacific Ocean
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Pictographs
Not Used
Used
Petroglyphs
Not Used
Used
Figurines
Used
Not Yet 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.
Hawaiite is a fine-grained, hard rock that forms when bits of lava shoot out of volcanoes and reach the Earth's surface.
Mineral Content
Augite, Feldspar, Hornblende, Nepheline, Olivine, Plagioclase, Pyroxene
Olivine, Plagioclase, Pyroxene
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
Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion
Not Applicable
Grain Size
Fine Grained
Not Applicable
Fracture
Conchoidal
Conchoidal
Streak
Black
Not Available
Porosity
Highly Porous
Less Porous
Luster
Not Available
Not Available
Compressive Strength
Not Available
Cleavage
Not Available
Not Applicable
Toughness
1.6
Not Available
Specific Gravity
Not Available
Not Available
Transparency
Opaque
Opaque
Density
Not Available
Not Available
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
Heat 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
Iceland
Others
Greenland
Hawaii Islands
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil, Colombia, Venezuela
Brazil
Deposits in Oceania Continent
Australia
New Zealand, Queensland
Not Yet Found
All about Essexite and Hawaiite Properties
Know all about Essexite and Hawaiite properties here. All properties of rocks are important as they define the type of rock and its application. Essexite and Hawaiite belong to Igneous Rocks.Texture of Essexite is Granular whereas that of Hawaiite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular. Essexite appears Banded and Hawaiite appears Dull and Soft. The luster of Essexite and Hawaiite is not available. Essexite is available in dark grey to black colors whereas Hawaiite is available in black, brown, light to dark grey colors. The commercial uses of Essexite are cemetery markers, commemorative tablets, jewelry, sea defence, tombstones and that of Hawaiite are creating artwork, sea defence.