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
Tachylite is a vitreous form of basaltic volcanic glass. This glass is formed naturally by the rapid cooling of molten basalt
Discoverer
Unknown
Unknown
Etymology
From Old French esclate, from esclat (French éclat)
From German Tachylite, from tachy- + Greek lutos soluble, melting
Class
Metamorphic Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Group
Not Applicable
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Medium Grained Rock, Opaque Rock
Texture
Foliated
Vitreous
Color
Black, Brown, Buff, Green, Light to Dark Grey, Purple, Red, Shades of Blue
Black, Dark Brown
Durability
Durable
Durable
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
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone
Cutting Tool, Knives, Landscaping, Scrapers
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Monuments, Sculpture, Small Figurines
Artifacts
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
Cemetery Markers, Creating Artwork
Types
Not Available
Not Available
Features
Easily splits into thin plates, Surfaces are often shiny, Very fine grained rock
Available in Lots of Colors and Patterns, Clasts are smooth to touch, NA
Archaeological Significance
Monuments
Used
Not Yet Used
Famous Monuments
Data Not Available
Not Applicable
Sculpture
Used
Not Yet Used
Famous Sculptures
Data Not Available
Not Applicable
Figurines
Used
Not Yet Used
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.
Tachylite 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.
Mineral Content
Apatite, Biotite, Chlorite, Feldspar, Graphite, Hematite, Kaolinite, Magnetite, Pyrite, Tourmaline, Zircon
Feldspar, Olivine
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Fe, Mg
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, Mechanical Weathering
Types of Erosion
Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Chemical Erosion, Sea Erosion, Water Erosion, Wind Erosion
Grain Size
Very fine-grained
Medium to Fine Coarse Grained
Fracture
Splintery
Conchoidal
Streak
Light to dark brown
Vermilion
Porosity
Less Porous
Less Porous
Cleavage
Slaty
Not Available
Toughness
1.2
Not Available
Specific Gravity
2.65-2.8
2.4
Transparency
Opaque
Opaque
Density
2.6-2.8 g/cm3
3.058 g/cm3
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Turkey
Cambodia, Russia, South Korea
Africa
Not Yet Found
East Africa
Europe
Belgium, France, Germany, Italy, Norway, Portugal, Spain, United Kingdom
England, Germany, Hungary, Iceland, Scotland, Sweden
Others
Arctic
Hawaii Islands
Deposits in Western Continents
South America
Brazil
Not Yet Found
Deposits in Oceania Continent
Australia
Not Yet Found
Victoria
All about Slate and Tachylite Properties
Know all about Slate and Tachylite properties here. All properties of rocks are important as they define the type of rock and its application. Slate belongs to Metamorphic Rocks while Tachylite belongs to Igneous Rocks.Texture of Slate is Foliated whereas that of Tachylite is Vitreous. Slate appears Dull and Tachylite appears Glassy. The luster of Slate is dull while that of Tachylite is resinous. Slate is available in black, brown, buff, green, light to dark grey, purple, red, shades of blue colors whereas Tachylite is available in black, dark brown 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 Tachylite are cemetery markers, creating artwork.