Definition
Gabbro is an intrusive igneous rock which is chemically equivalent to plutonic Basalt
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite
Discoverer
Christian Leopold von Buch
Unknown
Etymology
From Latin glaber bare, smooth, bald
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
Other Categories
Coarse Grained Rock, Opaque Rock
Medium Grained Rock, Opaque Rock
Texture
Phaneritic
Porphyritic
Color
Dark Grey to Black
Blue, Bluish - Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Veined and Shiny
Foliated
Interior Uses
Countertops, 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
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
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Cemetery Markers
Types
Anorthosite Gabbro and Norite Gabbro
Rhyolite
Features
Smooth to touch
Very fine grained rock, It is One of the Oldest, Strongest and Hardest Rock
Archaeological Significance
Formation
Gabbro, a mafic rock, forms due to cooling and crystallization of magma underneath Earth's surface.
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.
Mineral Content
Augite, Olivine, Plagioclase, Pyroxene
Albite, Amphibole, Quartz
Compound Content
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Al, Fe, Potassium Oxide
Types of Metamorphism
Impact Metamorphism
Cataclastic Metamorphism, Regional Metamorphism
Types of Weathering
Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Coastal Erosion
Coastal Erosion, Water Erosion
Grain Size
Coarse Grained
Medium Grained
Fracture
Conchoidal
Pervasive
Streak
Black
Bluish Black
Porosity
Highly Porous
Highly Porous
Specific Gravity
2.86-2.87
2.38
Transparency
Opaque
Opaque
Density
2.7-3.3 g/cm3
-9999 g/cm3
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Africa
South Africa
East Africa
Europe
Germany, Greece, Italy, Scotland, Turkey
Italy
Deposits in Western Continents
North America
Canada, USA
-
South America
Brazil, Colombia, Venezuela
-
Deposits in Oceania Continent
Australia
New Zealand, Queensland
Queensland