Definition
Granulite is fine to medium grained metamorphic rock with a granular of polygonal crystals.
Porphyry is a reddish-brown to purple igneous rock containing large phenocrysts of various minerals embedded in a fine-grained matrix
Origin
Central Europe
Egypt
Discoverer
Unknown
Unknown
Etymology
From Latin granulum, a little grain or fine grained
From Old French porfire, from Italian porfiro and in some cases directly from Latin porphyrites
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Granoblastic
Porphyritic
Color
Black, Brown
Black, Brown, Green, Grey, Red, Rust, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Veined or Pebbled
Dull
Interior Uses
Bathrooms, Countertops, Decorative Aggregates, Entryways, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Building houses or walls
Construction Aggregate
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Monuments, Sculpture
Commercial Uses
Curling, Gemstone, Laboratory bench tops, Soil Conditioner, Tombstones
Creating Artwork, Gemstone, Jewelry
Types
Metamorphic rock
Rhomb Porphyry
Features
Clasts are smooth to touch
Generally rough to touch, Is one of the oldest rock, Surfaces are often shiny
Archaeological Significance
Formation
Granulite is a fine-grained granular metamorphic rock in which the main component minerals are feldspars and quartz and forms at high temperature and pressure conditions.
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
Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Quartz
Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica
Compound Content
Aluminium Oxide, CaO, Carbon Dioxide, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Sulfur Dioxide, Titanium Dioxide
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
Biological Weathering, Chemical Weathering
Types of Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Grain Size
Medium to Coarse Grained
Fine Grained
Porosity
Very Less Porous
Less Porous
Specific Gravity
2.8-3.0
2.5-4
Transparency
Opaque
Translucent to Opaque
Density
3.06-3.33 g/cm3
2.5-2.52 g/cm3
Resistance
Heat Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
China, India, Iran, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Vietnam
China, Kazakhstan, South Korea, Thailand, Turkey, Vietnam
Africa
Angola, Egypt, Madagascar, Nigeria, South Africa
Egypt, Ethiopia, Ghana, South Africa
Europe
Austria, Belgium, Finland, France, Germany, Italy, Norway, Sardinia, Spain, Switzerland, The Czech Republic
Finland, France, Germany, Great Britain, Hungary, Iceland, Ireland, Italy, Netherlands, Norway, Romania, Sweden, Switzerland
Deposits in Western Continents
North America
Canada, USA
Canada, Cuba, Jamaica, USA
South America
-
Bolivia, Brazil, Colombia, Ecuador, Paraguay
Deposits in Oceania Continent
Australia
-
New South Wales, New Zealand, Western Australia
Granulite 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. Granulite vs Porphyry characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Granulite and Properties of Porphyry. Learn more about Granulite vs Porphyry in the next section. The interior uses of Granulite include Bathrooms, Countertops, Decorative aggregates, Entryways, Flooring, Homes, Hotels, Interior decoration, Kitchens and Stair treads whereas the interior uses of Porphyry include Decorative aggregates and Interior decoration. Due to some exceptional properties of Granulite and Porphyry, they have various applications in construction industry. The uses of Granulite in construction industry include As dimension stone, Building houses or walls and that of Porphyry include Construction aggregate.
More about Granulite and Porphyry
Here you can know more about Granulite and Porphyry. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Granulite and Porphyry consists of mineral content and compound content. The mineral content of Granulite includes Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Plagioclase, Quartz and mineral content of Porphyry includes Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica. You can also check out the list of all Metamorphic Rocks. When we have to compare Granulite vs Porphyry, the texture, color and appearance plays an important role in determining the type of rock. Granulite is available in black, brown colors whereas, Porphyry is available in black, brown, green, grey, red, rust, white colors. Appearance of Granulite is Veined or Pebbled and that of Porphyry is Dull. Properties of rock is another aspect for Granulite vs Porphyry. Hardness of Granulite and Porphyry is 6-7. The types of Granulite are Metamorphic rock 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 Granulite and Porphyry is white. The specific heat capacity of Granulite is 0.14 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.Granulite is heat resistant, wear resistant whereas Porphyry is heat resistant, impact resistant.