Definition
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
Oolite is a sedimentary rock formed from ooids, spherical grains which are composed of concentric layers of calcite
Discoverer
Unknown
William Smith
Etymology
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
From oo- + -lite, after German Oolit. A rock consisting of fine grains of carbonate of lime
Class
Igneous Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Porphyritic
Clastic or Non-Clastic
Color
Black, Brown, Green, Grey, Red, Rust, White
Black, Blue, Brown, Cream, Green, Grey, Pink, Red, Silver, White, Yellow
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull
Rounded and Rough
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
-
Construction Industry
Construction Aggregate
Cement Manufacture, Cobblestones, Landscaping
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts
Commercial Uses
Creating Artwork, Gemstone, Jewelry
Creating Artwork, Jewelry, Used in aquariums
Types
Rhomb Porphyry
Pisolitic Oolite and Oncolitic Oolite
Features
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Available in lots of colors, Generally rough to touch, Very fine grained rock
Archaeological Significance
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.
Oolites form when layers of calcite are deposited around a sand grain or fossil piece and are rolled around in calm water, which makes them round.
Mineral Content
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
Calcite, Chert, Clay, Dolomite, Quartz, Sand, Silt
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, Ca, NaCl, CaO, Iron(III) Oxide, FeO, MgO
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
-
Types of Weathering
Biological Weathering, Chemical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion
Grain Size
Fine Grained
Fine Grained
Fracture
Irregular
Conchoidal
Porosity
Less Porous
Less Porous
Luster
Dull
Pearly to Shiny
Specific Gravity
2.5-4
-9999
Transparency
Translucent to Opaque
Opaque
Density
2.5-2.52 g/cm3
-9999 g/cm3
Resistance
Heat Resistant, Impact Resistant
Heat Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
Africa
Egypt, Ethiopia, Ghana, South Africa
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Europe
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
United Kingdom
Deposits in Western Continents
North America
Canada, Cuba, Jamaica, USA
USA
South America
Bolivia, Brazil, Colombia, Ecuador, Paraguay
Colombia
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Western Australia
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula
All about Porphyry and Oolite Properties
Know all about Porphyry and Oolite properties here. All properties of rocks are important as they define the type of rock and its application. Porphyry belongs to Igneous Rocks while Oolite belongs to Sedimentary Rocks.Texture of Porphyry is Porphyritic whereas that of Oolite is Clastic or Non-Clastic. Porphyry appears Dull and Oolite appears Rounded and Rough. The luster of Porphyry is dull while that of Oolite is pearly to shiny. Porphyry is available in black, brown, green, grey, red, rust, white colors whereas Oolite is available in black, blue, brown, cream, green, grey, pink, red, silver, white, yellow colors. The commercial uses of Porphyry are creating artwork, gemstone, jewelry and that of Oolite are creating artwork, jewelry, used in aquariums.