Definition
Gabbro is an intrusive igneous rock which is chemically equivalent to plutonic Basalt
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
Origin
Germany
USA, Australia
Discoverer
Christian Leopold von Buch
Tornebohm
Etymology
From Latin glaber bare, smooth, bald
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Phaneritic
Earthy, Mud-rich, Rough
Color
Dark Grey to Black
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Veined and Shiny
Dull
Interior Uses
Countertops, Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Types
Anorthosite Gabbro and Norite Gabbro
Endoskarns
Features
Smooth to touch
Host Rock for Lead, Zinc and Copper Deposits
Archaeological Significance
Formation
Gabbro, a mafic rock, forms due to cooling and crystallization of magma underneath Earth's surface.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Augite, Olivine, Plagioclase, Pyroxene
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Compound Content
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Types of Metamorphism
Impact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Chemical Weathering
-
Types of Erosion
Coastal Erosion
-
Grain Size
Coarse Grained
Fine Grained
Fracture
Conchoidal
Irregular
Streak
Black
Light to dark brown
Porosity
Highly Porous
Less Porous
Specific Gravity
2.86-2.87
2.86
Transparency
Opaque
Opaque
Density
2.7-3.3 g/cm3
2.8-2.9 g/cm3
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
India, Russia
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Africa
South Africa
South Africa, Western Africa
Europe
Germany, Greece, Italy, Scotland, Turkey
United Kingdom
Deposits in Western Continents
North America
Canada, USA
Canada
South America
Brazil, Colombia, Venezuela
Brazil, Colombia, Paraguay
Deposits in Oceania Continent
Australia
New Zealand, Queensland
Central Australia, Western Australia
All about Gabbro and Skarn Properties
Know all about Gabbro and Skarn properties here. All properties of rocks are important as they define the type of rock and its application. Gabbro belongs to Igneous Rocks while Skarn belongs to Metamorphic Rocks.Texture of Gabbro is Phaneritic whereas that of Skarn is Earthy, Mud-rich, Rough. Gabbro appears Veined and Shiny and Skarn appears Dull. The luster of Gabbro is while that of Skarn is waxy and dull. Gabbro is available in dark grey to black colors whereas Skarn is available in black, brown, green, grey, white colors. The commercial uses of Gabbro are cemetery markers, commemorative tablets, laboratory bench tops, jewelry, sea defence, tombstones and that of Skarn are creating artwork, gemstone, jewelry, metallurgical flux, source of magnesia (mgo).