Definition
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
Metapelite is an old and currently not widely used field geological term for a clay rich fine-grained clastic sediment or sedimentary rock, i.e. mud or a mudstone
Discoverer
Unknown
Unknown
Etymology
From Alkalic Igneous complex near Loch Borralan in northwest Scotland
From Pelos or clay in Greek
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Granular
Foliated
Color
Brown, Buff, Cream, Green, Grey, Pink, White
Dark Greenish - Grey, Green, Light Green, Light Greenish Grey
Durability
Durable
Durable
Appearance
Banded and Foilated
Banded
Interior Uses
Countertops, Decorative Aggregates, Flooring, Homes, Interior Decoration
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone
Other Architectural Uses
Curbing
Curbing
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
Cement Manufacture, Construction Aggregate, for Road Aggregate
Antiquity Uses
Artifacts
Artifacts
Commercial Uses
Cemetery Markers
Commemorative Tablets, Creating Artwork
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
Easily splits into thin plates, It is One of the Oldest, Strongest and Hardest Rock
Archaeological Significance
Formation
Borolanites 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. Metapelite is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Albite, Amphibole, Biotite, Cancrinite, Feldspar, Hornblende, Plagioclase, Pyroxene, Sodalite
Albite, Chlorite, Quartz
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, CaO, MgO
Types of Metamorphism
Regional Metamorphism
-
Types of Weathering
Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Wind Erosion
Chemical Erosion, Coastal Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Medium to Fine Coarse Grained
Fracture
Conchoidal to Uneven
Fibrous
Porosity
Less Porous
Highly Porous
Luster
Greasy to Dull
Earthy
Specific Gravity
2.6
3.4-3.7
Transparency
Translucent to Opaque
Opaque
Density
2.6 g/cm3
0-300 g/cm3
Resistance
Heat Resistant, Impact Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant
Deposits in Eastern Continents
Asia
Indonesia, Iran, Russia, Saudi Arabia, Sri Lanka, Taiwan, Thailand, Turkey, Turkmenistan, Vietnam
-
Africa
Angola, Egypt, Madagascar, Namibia, Nigeria, South Africa
Western Africa
Europe
Andorra, Finland, France, Great Britain, Italy, Norway, Portugal, Spain, Sweden
United Kingdom
Deposits in Western Continents
North America
Canada, USA
-
South America
Brazil, Chile, Colombia, Uruguay, Venezuela
Brazil, Colombia, Ecuador
Deposits in Oceania Continent
Australia
New Zealand, Queensland, South Australia, Tasmania, Western Australia
Central Australia, Western Australia