Definition
Siltstone can be defined as a fine-grained sedimentary rock which mainly consists of consolidated silt
Theralite is a plutonic hylocrystalline igneous rock consisting of augite, olivine, calcic plagioclase and nepheline
Discoverer
Unknown
Unknown
Etymology
From English word silt and stone and from Proto-Indo-European root sal and stainaz
From Greek to pursue
Class
Sedimentary Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Group
Not Applicable
Plutonic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic
Phaneritic
Color
Brown, Red, Reddish Brown
Dark Grey to Black
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Rough
Veined and Shiny
Interior Uses
Decorative Aggregates, Interior Decoration
Decorative Aggregates, Flooring, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing
Curbing
Construction Industry
Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Making natural cement, Raw material for the manufacture of mortar
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
Medical Industry
Not Yet Used
Not Yet Used
Antiquity Uses
Artifacts, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Commercial Uses
Raw material for the manufacture of mortar, Soil Conditioner
Cemetery Markers, Commemorative Tablets, Creating Artwork, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Types
Not Available
Teschenite and Essexite
Features
Available in Lots of Colors and Patterns, Easily splits into thin plates, Generally rough to touch, High silica content, Very fine grained rock
Smooth to touch
Archaeological Significance
Monuments
Not Yet Used
Used
Famous Monuments
Not Applicable
Data Not Available
Famous Sculptures
Data Not Available
Data Not Available
Pictographs
Not Used
Not Used
Petroglyphs
Not Used
Not Used
Formation
Siltstone is a type of sedimentary rock which is formed from fine rock particles. As the particles of eroded rock travel along with water, the edges of the rock are worn-out by water into a rounded shape.
Theralite 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
Calcite, Clay, Clay Minerals, Feldspar, Micas, Quartz, Sand, Silica, Silt
Augite, Olivine, Plagioclase, Pyroxene
Compound Content
Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Types of Metamorphism
Not Applicable
Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Biological Weathering
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
Grain Size
Fine Grained
Fine Grained
Fracture
Conchoidal
Uneven, Splintery or Conchoidal
Porosity
Highly Porous
Highly Porous
Luster
Dull
Waxy and Dull
Cleavage
Not Available
Non-Existent
Specific Gravity
2.54-2.73
2.5-2.8
Transparency
Opaque
Translucent to Opaque
Density
2.6-2.7 g/cm3
2.7 g/cm3
Specific Heat Capacity
Not Available
Resistance
Heat Resistant, Impact Resistant, Pressure Resistant, Water Resistant
Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
China, India, Kazakhstan, Mongolia, Russia, Uzbekistan
India, Russia
Africa
Namibia, Nigeria, South Africa
South Africa
Europe
Austria, Denmark, Germany, Great Britain, Netherlands, Norway, Poland, Sweden, Switzerland, United Kingdom
Germany, Greece, Italy, Scotland, Turkey
Others
Greenland
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
Canada, USA
Canada, USA
South America
Brazil
Bolivia, Brazil, Colombia, Venezuela
Deposits in Oceania Continent
Australia
New South Wales, New Zealand
New Zealand, Queensland