Definition
Oolite is a sedimentary rock formed from ooids, spherical grains which are composed of concentric layers of calcite
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
Discoverer
William Smith
Unknown
Etymology
From oo- + -lite, after German Oolit. A rock consisting of fine grains of carbonate of lime
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic or Non-Clastic
Porphyritic
Color
Black, Blue, Brown, Cream, Green, Grey, Pink, Red, Silver, White, Yellow
Black, Brown, Green, Grey, Red, Rust, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Rounded and Rough
Dull
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Garden Decoration, Paving Stone
Other Architectural Uses
-
Curbing
Construction Industry
Cement Manufacture, Cobblestones, Landscaping
Construction Aggregate
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Creating Artwork, Jewelry, Used in aquariums
Creating Artwork, Gemstone, Jewelry
Types
Pisolitic Oolite and Oncolitic Oolite
Rhomb Porphyry
Features
Available in lots of colors, Generally rough to touch, Very fine grained rock
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Archaeological Significance
Formation
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.
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.
Mineral Content
Calcite, Chert, Clay, Dolomite, Quartz, Sand, Silt
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
Compound Content
Aluminium Oxide, Ca, NaCl, CaO, Iron(III) Oxide, FeO, MgO
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
-
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Fine Grained
Fine Grained
Fracture
Conchoidal
Irregular
Porosity
Less Porous
Less Porous
Luster
Pearly to Shiny
Dull
Specific Gravity
-9999
2.5-4
Transparency
Opaque
Translucent to Opaque
Density
-9999 g/cm3
2.5-2.52 g/cm3
Resistance
Heat Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
Africa
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Egypt, Ethiopia, Ghana, South Africa
Europe
United Kingdom
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
Deposits in Western Continents
North America
USA
Canada, Cuba, Jamaica, USA
South America
Colombia
Bolivia, Brazil, Colombia, Ecuador, Paraguay
Deposits in Oceania Continent
Australia
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula
New South Wales, New Zealand, Western Australia
Oolite vs Porphyry Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Oolite vs Porphyry characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Oolite and Properties of Porphyry. Learn more about Oolite vs Porphyry in the next section. The interior uses of Oolite include Decorative aggregates, Flooring and Interior decoration whereas the interior uses of Porphyry include Decorative aggregates and Interior decoration. Due to some exceptional properties of Oolite and Porphyry, they have various applications in construction industry. The uses of Oolite in construction industry include Cement manufacture, Cobblestones, Landscaping and that of Porphyry include Construction aggregate.
More about Oolite and Porphyry
Here you can know more about Oolite and Porphyry. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Oolite and Porphyry consists of mineral content and compound content. The mineral content of Oolite includes Calcite, Chert, Clay, Dolomite, Quartz, Sand, Silt and mineral content of Porphyry includes Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica. You can also check out the list of all Sedimentary Rocks. When we have to compare Oolite vs Porphyry, the texture, color and appearance plays an important role in determining the type of rock. Oolite is available in black, blue, brown, cream, green, grey, pink, red, silver, white, yellow colors whereas, Porphyry is available in black, brown, green, grey, red, rust, white colors. Appearance of Oolite is Rounded and Rough and that of Porphyry is Dull. Properties of rock is another aspect for Oolite vs Porphyry. The hardness of Oolite is 3-4 and that of Porphyry is 6-7. The types of Oolite are Pisolitic Oolite and Oncolitic Oolite whereas types of Porphyry are Rhomb Porphyry. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Oolite and Porphyry is white. The specific heat capacity of Oolite is 0.65 kJ/Kg K and that of Porphyry is 0.71 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Oolite is heat resistant, wear resistant whereas Porphyry is heat resistant, impact resistant.