Definition
Foidolite is a rare type of coarse-grained intrusive igneous rock with a feldspathoid mineral content greater than 60%
Borolanite is a variety of Nepheline Syenite and belongs to igneous rocks and contains nepheline-alkali feldspar pseudomorphs which occur as conspicuous white spots in the dark rock matrix
Discoverer
Unknown
Unknown
Etymology
From the mineral feldspathoid which is the main content of rock
From Alkalic Igneous complex near Loch Borralan in northwest Scotland
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Color
Black, Brown, Green, Grey, Pink, White
Brown, Buff, Cream, Green, Grey, Pink, White
Durability
Durable
Durable
Appearance
Dull
Banded and Foilated
Interior Uses
Decorative Aggregates, Interior Decoration
Countertops, Decorative Aggregates, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Cement Manufacture, for Road Aggregate
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
Medical Industry
Taken as a Supplement for Calcium or Magnesium
-
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork
Cemetery Markers
Features
Host Rock for Lead
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
Archaeological Significance
Formation
Foidolites is a fine-grained, hard rock which is a type of metasomatite, essentially altered basalt. It forms with or without crystallization, either below the surface as intrusive rocks or on the surface as extrusive rocks.
Borolanites are formed due to alkaline igneous activities and are generally formed in thick continental crustal areas or in Cordilleran subduction zones.
Mineral Content
Amphibole, Biotite, Feldspar, Olivine, Plagioclase, Pyroxene
Albite, Amphibole, Biotite, Cancrinite, Feldspar, Hornblende, Plagioclase, Pyroxene, Sodalite
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism
Regional Metamorphism
Types of Weathering
-
Chemical Weathering, Mechanical Weathering
Types of Erosion
-
Wind Erosion
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Fracture
Conchoidal
Conchoidal to Uneven
Porosity
Very Less Porous
Less Porous
Luster
Subvitreous to Dull
Greasy to Dull
Specific Gravity
2.86
2.6
Transparency
Translucent
Translucent to Opaque
Density
-9999 g/cm3
2.6 g/cm3
Resistance
Heat Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Russia
Indonesia, Iran, Russia, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Turkmenistan, Vietnam
Africa
South Africa, Western Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Europe
-
Andorra, Finland, France, Great Britain, Italy, Norway, Portugal, Spain, Sweden
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
-
Brazil, Chile, Colombia, Uruguay, Venezuela
Deposits in Oceania Continent
Australia
Central Australia, Western Australia
New Zealand, Queensland, South Australia, Tasmania, Western Australia