Definition
Phonolite is an uncommon extrusive igneous rock volcanic rock of intermediate chemical composition between felsic and mafic
  
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
  
History
  
  
Origin
Unknown
  
USA, Australia
  
Discoverer
Unknown
  
Tornebohm
  
Etymology
From the Greek meaning sounding stone because of the metallic sound it produces if an unfractured plate is hit
  
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
  
Class
Igneous Rocks
  
Metamorphic Rocks
  
Sub-Class
Durable Rock, Medium Hardness Rock
  
Durable Rock, Hard Rock
  
Family
  
  
Group
Not Applicable
  
Not Applicable
  
Other Categories
Fine Grained Rock, Opaque Rock
  
Fine Grained Rock, Opaque Rock
  
Texture
Granular
  
Earthy, Mud-rich, Rough
  
Color
Brown, Buff, Cream, Green, Grey, Pink, White
  
Black, Brown, Colourless, Green, Grey, White
  
Maintenance
Less
  
Less
  
Durability
Durable
  
Durable
  
Water Resistant
Yes
  
Yes
  
Scratch Resistant
Yes
  
Yes
  
Stain Resistant
Yes
  
No
  
Wind Resistant
No
  
Yes
  
Acid Resistant
Yes
  
Yes
  
Appearance
Banded and Foilated
  
Dull
  
Architecture
  
  
Interior Uses
Countertops, Decorative Aggregates, Flooring, Homes
  
Decorative Aggregates, Entryways, Interior Decoration
  
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings, Paving Stone
  
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
  
Other Architectural Uses
Curbing
  
Curbing
  
Industry
  
  
Construction Industry
As Dimension Stone, Cement Manufacture, Construction Aggregate, for Road Aggregate, Landscaping, Making natural cement, Manufacture of Magnesium and Dolomite Refractories, Production of Glass and Ceramics
  
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
  
Medical Industry
Not Yet Used
  
Not Applicable
  
Antiquity Uses
Artifacts, Monuments, Sculpture
  
Artifacts, Monuments, Sculpture
  
Other Uses
  
  
Commercial Uses
Cemetery Markers, Creating Artwork
  
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
  
Types
Kenyte
  
Endoskarns
  
Features
Application of acids on the surface causes cloudy frosting, Available in Lots of Colors and Patterns, Dissolves in hydrochloric acid, Is one of the oldest rock
  
Host Rock for Lead, Zinc and Copper Deposits
  
Archaeological Significance
  
  
Monuments
Used
  
Used
  
Famous Monuments
Data Not Available
  
Data Not Available
  
Sculpture
Used
  
Used
  
Famous Sculptures
Data Not Available
  
Data Not Available
  
Pictographs
Used
  
Not Used
  
Petroglyphs
Used
  
Not Used
  
Figurines
Used
  
Used
  
Fossils
Absent
  
Absent
  
Formation
Phonolite are formed due to alkaline igneous activities and are generally formed in thick continental crustal areas or in Cordilleran subduction zones.
  
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
  
Composition
  
  
Mineral Content
Albite, Amphibole, Biotite, Cancrinite, Feldspar, Hornblende, Plagioclase, Pyroxene, Sodalite
  
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
  
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
  
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
  
Transformation
  
  
Metamorphism
Yes
  
Yes
  
Types of Metamorphism
Contact Metamorphism
  
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
  
Weathering
Yes
  
No
  
Types of Weathering
Chemical Weathering, Mechanical Weathering
  
Not Applicable
  
Erosion
Yes
  
No
  
Types of Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
  
Not Applicable
  
Physical Properties
  
  
Hardness
5.5-6
  
6.5
  
Grain Size
Fine Grained
  
Fine Grained
  
Fracture
Conchoidal to Uneven
  
Irregular
  
Streak
White
  
Light to dark brown
  
Porosity
Less Porous
  
Less Porous
  
Luster
Greasy to Dull
  
Waxy and Dull
  
Compressive Strength
150.00 N/mm
2
  
14
Not Available
  
Cleavage
Poor
  
Slaty
  
Toughness
Not Available
  
2.4
  
Specific Gravity
2.6
  
2.86
  
Transparency
Translucent to Opaque
  
Opaque
  
Density
2.6 g/cm3
  
2.8-2.9 g/cm3
  
Thermal Properties
  
  
Specific Heat Capacity
Not Available
  
0.92 kJ/Kg K
  
10
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
  
Heat Resistant
  
Deposits in Eastern Continents
  
  
Asia
Indonesia, Iran, Russia, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Turkmenistan, Vietnam
  
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
  
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
  
South Africa, Western Africa
  
Europe
Andorra, Finland, France, Germany, Great Britain, Italy, Norway, Portugal, Spain, Sweden
  
United Kingdom
  
Others
Greenland
  
Not Yet Found
  
Deposits in Western Continents
  
  
North America
Canada, USA
  
Canada
  
South America
Brazil, Chile, Colombia, Uruguay, Venezuela
  
Brazil, Colombia, Paraguay
  
Deposits in Oceania Continent
  
  
Australia
New Zealand, Queensland, South Australia, Tasmania, Western Australia
  
Central Australia, Western Australia