Definition
Schist is a medium grade metamorphic rock with medium to large, flat, sheet like grains in a preferred orientation
Claystone is a fine-grained, dark gray to pink sedimentary rock which mainly consists of compacted and hardened clay
Discoverer
Unknown
Unknown
Etymology
From French schiste, Greek skhistos i.e. split
From English clay and stone as the rock contains more amount of clay
Class
Metamorphic Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Other Categories
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Foliated, Platy
Clastic
Color
Black, Blue, Brown, Dark Brown, Green, Grey, Silver
Black, Blue, Brown, Green, Grey, Orange, Red, White, Yellow
Durability
Durable
Durable
Appearance
Layered and Shiny
Rough and Dull
Interior Uses
Decorative Aggregates, Floor Tiles, Interior Decoration
Decorative Aggregates, Entryways, Floor Tiles, Homes, Interior Decoration
Exterior Uses
Garden Decoration, Paving Stone
As Facing Stone, Roof Tiles
Other Architectural Uses
-
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, for Road Aggregate, Roadstone
As a Sintering Agent in Steel Industry to process Iron Ore, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
Antiquity Uses
Artifacts
Artifacts, Sculpture, Small Figurines
Commercial Uses
Used in aquariums, Writing Slates
Pottery
Types
Mica Schists, Calc-Silicate Schists, Graphite Schists, Blueschists, Whiteschists, Greenschists, Hornblende Schist, Talc Schist, Chlorite Schist, Garnet Schist, Glaucophane schist.
Claystone
Features
Easily splits into thin plates, Smooth to touch
Available in Lots of Colors and Patterns, Smooth to touch, Very fine grained rock
Archaeological Significance
Formation
Schist formed by dynamic metamorphism at high temperatures and pressures that aligns the grains of mica, hornblende and other elongated minerals into thin layers.
Claystone is generally quite soft, but can be hard and brittle. It forms due to weathering of mudstone.
Mineral Content
Alusite, Amphibole, Biotite, Chlorite, Epidote, Feldspar, Garnet, Graphite, Hornblade, Kyanite, Micas, Muscovite or Illite, Porphyroblasts, Quartz, Sillimanite, Staurolite, Talc
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
Compound Content
CaO, Carbon Dioxide, MgO
Aluminium Oxide, Ca, NaCl, CaO, Iron(III) Oxide, MgO, Silicon Dioxide
Types of Metamorphism
-
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Coastal Erosion, Water Erosion
Grain Size
Medium to Fine Coarse Grained
Fine Grained
Porosity
Highly Porous
Very Less Porous
Specific Gravity
2.5-2.9
0
Transparency
Opaque
Opaque
Density
2.8-2.9 g/cm3
2-2.9 g/cm3
Resistance
Impact Resistant, Pressure Resistant, Water Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
Afghanistan, Bangladesh, Bhutan, China, India, Japan, Kazakhstan, Malaysia, Pakistan, Russia, Thailand, Turkey, Vietnam
Bangladesh, China, India, Russia
Africa
Egypt, Ethiopia, Morocco, Nigeria, South Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
Europe
Austria, England, France, Georgia, Germany, Italy, Liechtenstein, Monaco, Norway, Slovenia, Spain, Sweden, Switzerland
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Deposits in Western Continents
North America
Canada, Costa Rica, Cuba, Mexico, Panama, USA
Canada, Panama, USA
South America
Brazil, Colombia, Guyana
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland
New South Wales, New Zealand, Queensland, Victoria, Western Australia