Definition
Trachyte is a grey fine-grained volcanic rock which mainly consists of alkali feldspar
Hawaiite is volcanic rock that resembles basalt. It is an olivine basalt with intermediate composition between alkali olivine and mugearite
Origin
Unknown
Hawaii Islands
Discoverer
Alexandre Brongniart and René Just Haüy
Joseph Iddings
Etymology
From Greek trakhus rough’ or trakhutēs roughness
From Hawaii Islands
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Opaque Rock
Texture
Aphanitic to Porphyritic
Glassy, Massive, Porphyritic, Scoriaceous, Vesicular
Color
Black, Brown, Dark Greenish - Grey, Green, Grey, Light to Dark Grey, White
Black, Brown, Light to Dark Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Banded
Dull and Soft
Interior Uses
Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
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, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
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, Creating Artwork
Creating Artwork, Sea Defence
Types
Not Available
Not Available
Features
Available in Lots of Colors and Patterns, Is one of the oldest rock, Matrix variable
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
Figurines
Used
Not Yet Used
Formation
Trachyte is an igneous volcanic rock with an aphanitic to porphyritic texture. It is the volcanic equivalent of syenite rock and forms as a result of magmatic differentiation.
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, Biotite, Feldspar, Hornblade, Plagioclase, Quartz
Olivine, Plagioclase, Pyroxene
Compound Content
Potassium Oxide, Sodium Oxide, Silicon Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Regional Metamorphism
Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Sea Erosion, Water Erosion, Wind Erosion
Not Applicable
Grain Size
Fine Grained
Not Applicable
Fracture
Not Available
Conchoidal
Streak
White
Not Available
Porosity
Less Porous
Less Porous
Luster
Metallic
Not Available
Cleavage
Not Available
Not Applicable
Toughness
Not Available
Not Available
Specific Gravity
2.7
Not Available
Transparency
Opaque
Opaque
Density
2.43-2.45 g/cm3
Not Available
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
Heat Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
India, Russia
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
South Africa
Europe
Bulgaria, England, Germany, Norway, Romania, Switzerland
Iceland
Others
Not Yet Found
Hawaii Islands
Deposits in Western Continents
North America
USA
Canada, USA
South America
Brazil, Chile
Brazil
Deposits in Oceania Continent
Australia
New Zealand, Queensland, South Australia, Western Australia
Not Yet Found