Definition
Pyroxenite is a dark, greenish, granular intrusive igneous rock consisting mainly of pyroxenes and olivine
Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks
Discoverer
Unknown
Unknown
Etymology
From pyro- fire + Greek xenos stranger as the mineral group was new to igneous rocks
From the Middle High German verb gneist (to spark; so called because the rock glitters)
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Clastic, Granular, Phaneritic, Porphyritic
Banded, Foliated, Platy
Color
Black to Grey, Bluish - Grey, Dark Greenish - Grey, Green, Light Greenish Grey
Black, Brown, Pink, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Foliated
Interior Uses
Countertops, Decorative Aggregates, Interior Decoration, Kitchens
Countertops, Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, As Facing 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 Dimension Stone
Antiquity Uses
Artifacts
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Cemetery Markers, Jewelry, Tombstones, Used in aquariums
Types
Clinopyroxenites, Orthopyroxenites and Websterites
Augen Gneiss, Henderson Gneiss, Lewisian Gneiss, Archean and Proterozoic Gneiss.
Features
Generally rough to touch, Host rock for Diamond, Is one of the oldest rock
Generally rough to touch, Is one of the oldest rock
Archaeological Significance
Famous Monuments
-
Konark Sun Temple in India, Washington Monument, US
Formation
Pyroxenites are ultramafic igneous rocks which are made up of minerals of the pyroxene group, such as augite and diopside, hypersthene, bronzite or enstatite.
Gneiss is a high grade metamorphic rock i.e. it has been subjected to higher temperatures and pressures than schist. It is formed by the metamorphosis of Gneiss forms from volcanic rock, shale or granitie.
Mineral Content
Amphibole, Augite, Bronzite, Chromite, Diopside, Enstatite, Garnet, Hornblende, Hypersthene, Magnetite, Pyroxene
Biotite, Chlorite, Feldspar, Garnet, Graphite, Hornblade, Micas, Muscovite or Illite, Quartz, Quartzite, Silica, Zircon
Compound Content
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, Magnesium Carbonate, MgO, MnO, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Impact Metamorphism, Regional Metamorphism
Impact Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion
Chemical Erosion, Coastal Erosion, Sea Erosion
Grain Size
Coarse Grained
Medium to Coarse Grained
Fracture
Uneven
Irregular
Streak
White, Greenish White or Grey
White
Porosity
Less Porous
Very Less Porous
Luster
Dull to Vitreous to Submetallic
Dull
Specific Gravity
3.2-3.5
2.5-2.7
Transparency
Opaque
Translucent to Opaque
Density
3.1-3.6 g/cm3
2.6-2.9 g/cm3
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Pressure Resistant, Scratch Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
India, Russia
China, India, Iran, Iraq, Kazakhstan, Kyrgyzstan, Mongolia, Russia
Africa
South Africa
Cameroon, Ethiopia, Ghana, Kenya, Madagascar, Morocco, Mozambique, Namibia, Nigeria, Tanzania, Togo
Europe
Germany, Greece, Italy, Scotland, Turkey
Albania, Austria, Bosnia and Herzegovina, Finland, France, Georgia, Germany, Hungary, Italy, Kosovo, Monaco, Norway, Poland, Romania, Serbia, Slovakia, Slovenia, Switzerland, Ukraine, United Kingdom
Deposits in Western Continents
North America
Canada, USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
Brazil, Colombia, Venezuela
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New Zealand, Queensland
New South Wales, New Zealand, Queensland, Victoria
All about Pyroxenite and Gneiss Properties
Know all about Pyroxenite and Gneiss properties here. All properties of rocks are important as they define the type of rock and its application. Pyroxenite belongs to Igneous Rocks while Gneiss belongs to Metamorphic Rocks.Texture of Pyroxenite is Clastic, Granular, Phaneritic, Porphyritic whereas that of Gneiss is Banded, Foliated, Platy. Pyroxenite appears Layered, Banded, Veined and Shiny and Gneiss appears Foliated. The luster of Pyroxenite is dull to vitreous to submetallic while that of Gneiss is dull. Pyroxenite is available in black to grey, bluish - grey, dark greenish - grey, green, light greenish grey colors whereas Gneiss is available in black, brown, pink, red, white colors. The commercial uses of Pyroxenite are cemetery markers, commemorative tablets, laboratory bench tops, jewelry, sea defence, tombstones and that of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums.