Definition
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
Quartzite is a non-foliated metamorphic rock that forms by the metamorphism of pure quartz Sandstone
Discoverer
Unknown
Unknown
Etymology
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
From quartz + -ite
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Group
Plutonic
Not Applicable
Other Categories
Fine Grained Rock, Opaque Rock
Medium Grained Rock, Opaque Rock
Texture
Porphyritic
Foliated, Granular
Color
Black, Brown, Colourless, Green, Grey, Red, Rust, White
Black, Blue, Brown, Green, Light Grey, Purple, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Interior Uses
Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Flooring, Homes
Exterior Uses
Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
Construction Aggregate
Arrowheads, As Dimension Stone, Cement Manufacture, Construction Aggregate, Cutting Tool, for Road Aggregate, Making natural cement, Production of Glass and Ceramics, Rail Track Ballast, Roadstone
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Jewellery, Monuments, Sculpture
Commercial Uses
Creating Artwork, Gemstone, Jewelry
An Oil and Gas Reservoir, As armour rock for sea walls, Cemetery Markers, Commemorative Tablets, In aquifers, Laboratory bench tops, Petroleum reservoirs, Soil Conditioner, Source of Magnesia (MgO), Tombstones, Used in aquariums
Types
Rhomb Porphyry
Not Available
Features
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Generally rough to touch, Is one of the oldest rock
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Formation
Porphyry is formed in two stages: the magma cools slowly deep within the crust or the magma is cools rapidly as it erupts from a volcano, creating small grains that are usually invisible to naked eye.
Quartzite forms from sandstone and the mineral quartz being put under extreme heat and pressure.
Mineral Content
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
Chlorite, Epidote, Hematite, Kyanite, Magnetite, Muscovite or Illite, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, Iron(III) Oxide, MgO, Sodium Oxide, Silicon Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Hydrothermal Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Not Registered
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Medium Grained
Fracture
Irregular
Uneven, Splintery or Conchoidal
Porosity
Less Porous
Less Porous
Compressive Strength
Not Available
Cleavage
Imperfect
Indiscernible
Specific Gravity
2.5-4
2.6-2.8
Transparency
Translucent to Opaque
Transparent to Translucent
Density
2.5-2.52 g/cm3
2.32-2.42 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
China, India, Israel, Russia, South Korea, Thailand, Turkey
Africa
Egypt, Ethiopia, Ghana, South Africa
Ethiopia, Morocco, South Africa, Zimbabwe
Europe
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
England, Italy, Norway, Scotland, Sweden, United Kingdom
Others
Greenland
Greenland
Deposits in Western Continents
North America
Canada, Cuba, Jamaica, USA
Bahamas, Canada, USA
South America
Bolivia, Brazil, Colombia, Ecuador, Paraguay
Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Western Australia
New Zealand, Queensland, Western Australia
All about Porphyry and Quartzite Properties
Know all about Porphyry and Quartzite properties here. All properties of rocks are important as they define the type of rock and its application. Porphyry belongs to Igneous Rocks while Quartzite belongs to Metamorphic Rocks.Texture of Porphyry is Porphyritic whereas that of Quartzite is Foliated, Granular. Porphyry appears Dull and Quartzite appears Lustrous. The luster of Porphyry is dull while that of Quartzite is vitreous. Porphyry is available in black, brown, colourless, green, grey, red, rust, white colors whereas Quartzite is available in black, blue, brown, green, light grey, purple, white, yellow colors. The commercial uses of Porphyry are creating artwork, gemstone, jewelry and that of Quartzite are an oil and gas reservoir, as armour rock for sea walls, cemetery markers, commemorative tablets, in aquifers, laboratory bench tops, petroleum reservoirs, soil conditioner, source of magnesia (mgo), tombstones, used in aquariums.