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
Whiteschist is an uncommon rock type belonging to a class of metamorphic rock, this is formed at high-ultra-high pressures
History
Origin
England
Tasmania
Discoverer
Abraham Gottlob Werner
Unknown
Etymology
From Old French esclate, from esclat (French éclat)
From French schiste, Greek skhistos i.e. split
Class
Metamorphic Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Soft Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Foliated
Foliated
Color
Black, Brown, Buff, Green, Light to Dark Grey, Purple, Red, Shades of Blue
Green, Grey, White
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull
Banded and Foilated
Architecture
Interior Uses
Bathrooms, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Homes, Hotels, Interior Decoration, Kitchens, Stair Treads
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Industry
Construction Industry
As Dimension Stone
for Road Aggregate
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture, Small Figurines
Other Uses
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
Creating Artwork, Gemstone, Jewelry, Production of Lime
Types
Phyllite, Schist, and Slate
-
Features
Easily splits into thin plates, Surfaces are often shiny, Very fine grained rock
High percentage of mica, Host Rock for Lead
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Absent
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.
Whiteschist is formed by dynamic metamorphism at high temperatures and pressures that aligns the grains of mica, hornblende and other elongated minerals into thin layers.
Composition
Mineral Content
Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon
Carbonate, Coesite, Quartz, Silica
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
CaO, Mg, MgO, Silicon Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Regional Metamorphism
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Physical Properties
Hardness
3-41.5
1
7
👆🏻
Grain Size
Very fine-grained
Fine to Medium Grained
Fracture
Splintery
Conchoidal
Streak
Light to dark brown
White
Porosity
Less Porous
Less Porous
Luster
Dull
Subvitreous to Dull
Compressive Strength
30.00 N/mm2200.00 N/mm2
0.15
450
👆🏻
Cleavage
Slaty
Perfect
Toughness
1.2
1
Specific Gravity
2.65-2.82.86
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.6-2.8 g/cm32.8-2.9 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.76 kJ/Kg K0.92 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
China, India, Turkey
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
Africa
-
Egypt, Ethiopia, Morocco, Nigeria, South Africa
Europe
Belgium, France, Germany, Italy, Norway, Portugal, Spain, United Kingdom
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Others
Arctic
-
Deposits in Western Continents
North America
USA
Canada, Costa Rica, Cuba, Mexico, Panama, USA
South America
Brazil
Brazil, Colombia, Guyana
Deposits in Oceania Continent
Australia
-
New South Wales, New Zealand, Queensland