Definition
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism
Minette is a variety of Lamprophyre and is porphyritic alkaline igneous rock which is mainly dominated by biotite and potassic feldspar
Discoverer
Unknown
Unknown
Etymology
From Old French esclate, from esclat (French éclat)
From French mine ore, mine + ette
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Texture
Foliated
Porphyritic
Color
Black, Brown, Buff, Green, Light to Dark Grey, Purple, Red, Shades of Blue
Black, Bluish - Grey, Brown, Dark Greenish - Grey, Green, Grey
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Dull
Dull, Banded and Foilated
Interior Uses
Bathrooms, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Countertops, Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
Not Yet Used
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Commercial Uses
Blackboards, Commemorative Tablets, Laboratory bench tops, Standard material for the bed of Billiard table, Standard material for the beds of Pool and Snooker table, Tombstones, Used in aquariums, Writing Slates
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO)
Types
Not Available
Minette, Alnoite, Camptonite, Monchiquite, Fourchite, Vogesite, Appinite and Spessartite
Features
Easily splits into thin plates, Surfaces are often shiny, Very fine grained rock
Always found as volcanic pipes over deep continental crust, Host rock for Diamond, Is one of the oldest rock, Surfaces are often shiny
Archaeological Significance
Famous Monuments
Data Not Available
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Formation
Slate is a low grade metamorphic rock that is generally formed by metamorphosis of mudstone or shale, under relatively low pressure and temperature conditions.
Minette formation takes place deep beneath the Earth’s surface at around 150 to 450 kms, and are erupted rapidly and violently.
Mineral Content
Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon
Amphibole, Carbonate, Garnet, Micas, Olivine, Phlogopite, Pyroxene
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional 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
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Sea Erosion, Wind Erosion
Grain Size
Very fine-grained
Fine to Coarse Grained
Fracture
Splintery
Conchoidal
Streak
Light to dark brown
White
Porosity
Less Porous
Very Less Porous
Luster
Dull
Subvitreous to Dull
Compressive Strength
Not Available
Cleavage
Slaty
Conchoidal
Toughness
1.2
Not Available
Specific Gravity
2.65-2.8
2.86-2.87
Transparency
Opaque
Translucent to Opaque
Density
2.6-2.8 g/cm3
2.95-2.96 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
China, India, Turkey
Russia
Africa
Not Yet Found
Angola, Botswana, Cameroon, Ethiopia, South Africa
Europe
Belgium, France, Germany, Italy, Norway, Portugal, Spain, United Kingdom
England, Hungary, Iceland, United Kingdom
Others
Arctic
Antarctica, Greenland
Deposits in Western Continents
North America
USA
Canada, Mexico, USA
South America
Brazil
Argentina, Colombia, Ecuador
Deposits in Oceania Continent
Australia
Not Yet Found
New South Wales, New Zealand, Queensland, South Australia, Western Australia
All about Slate and Minette Properties
Know all about Slate and Minette properties here. All properties of rocks are important as they define the type of rock and its application. Slate belongs to Metamorphic Rocks while Minette belongs to Igneous Rocks.Texture of Slate is Foliated whereas that of Minette is Porphyritic. Slate appears Dull and Minette appears Dull, Banded and Foilated. The luster of Slate is dull while that of Minette is subvitreous to dull. Slate is available in black, brown, buff, green, light to dark grey, purple, red, shades of blue colors whereas Minette is available in black, bluish - grey, brown, dark greenish - grey, green, grey colors. The commercial uses of Slate are blackboards, commemorative tablets, laboratory bench tops, standard material for the bed of billiard table, standard material for the beds of pool and snooker table, tombstones, used in aquariums, writing slates and that of Minette are an oil and gas reservoir, as a feed additive for livestock, gemstone, metallurgical flux, production of lime, soil conditioner, source of magnesia (mgo).