Definition
Argillites are highly compact sedimentary or slightly metamorphosed rocks that consist largely or wholly of particles of clay or silt but lack the fissility of shale or the cleavage characteristic of slate
Travertine is a mineral consisting of layered calcium carbonate formed by deposition from spring waters
History
Origin
-
Italy
Discoverer
Unknown
Marcus Vitruvius Pollio
Etymology
From Latin Argilla (clay) and -ite in English which became agrilla+ -ite = Argillite
From Italian travertino a kind of building stone, from Tiburs, adjective from Tibur (Tivoli), in Italy
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Soft Rock
Durable Rock, Medium Hardness Rock
Family
Group
-
-
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic, Polished
Banded
Color
Dark Grey to Black, Pink, Red, White
Beige, Black, Blue, Brown, Grey, Red, White, Yellow
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Rough and Dull
Fibrous
Architecture
Interior Uses
Decorative Aggregates, Homes, Interior Decoration
Decorative Aggregates, Entryways, Flooring, Homes, Interior Decoration
Exterior Uses
As Building Stone, Garden Decoration, Office Buildings
As Building Stone, As Facing Stone, Paving Stone, Garden Decoration, Office Buildings
Other Architectural Uses
Curbing, Whetstones
Curbing
Industry
Construction Industry
Used for flooring, stair treads, borders and window sills.
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate, Raw material for the manufacture of mortar
Medical Industry
-
-
Antiquity Uses
Artifacts, Monuments, Sculpture
Artifacts, Jewellery, Monuments, Sculpture, Small Figurines
Other Uses
Commercial Uses
Fire resistant, Used to manufracture paperweights and bookends
Cemetery Markers, Creating Artwork, Gemstone, Jewelry, Paper Industry, Pottery
Types
Metamorphic rock
Thermal Travertine and Tufa
Features
Is one of the oldest rock
Stalactites and stalagmites are formed from this rock, Surfaces are often shiny, Very fine grained rock
Archaeological Significance
Monuments
-
-
Famous Monuments
-
Colosseum in Rome, Italy, Sacré Coeur in Paris, France, Trevi Fountain in Rome, Italy
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Present
Present
Formation
An argillite is a fine-grained sedimentary rock mainly composed of clay particles which forms from lithified muds which contain variable amounts of silt-sized particles.
Travertine is a type of sedimentary rock formed when a river carries or transports pieces of broken rock which then undergo sedimentation. They are then subjected to high temperature and pressure hence forming travertine rock.
Composition
Mineral Content
Biotite, Chlorite, Feldspar, Micas, Muscovite or Illite, Plagioclase, Pyrite, Quartz
Calcite, Clay, Feldspar, Micas, Quartz
Compound Content
Iron(III) Oxide, Potassium Oxide, MgO, Silicon Dioxide
Ca, NaCl, CaO, Oxygen
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
-
-
Weathering
✔
✘
✔
✘
Types of Weathering
Biological Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Chemical Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion
Physical Properties
Hardness
2-33-4
1
7
👆🏻
Grain Size
Fine Grained
Fine Grained
Fracture
Conchoidal to Uneven
Splintery
Streak
White to Grey
White
Porosity
Highly Porous
Highly Porous
Luster
Waxy and Dull
Dull to Pearly
Compressive Strength
-80.00 N/mm2
0.15
450
👆🏻
Cleavage
Slaty
-
Toughness
2.6
1
Specific Gravity
2.56-2.681.68
0
8.4
👆🏻
Transparency
Opaque
Opaque
Density
2.54-2.66 g/cm32.71 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.87 kJ/Kg K1.09 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Impact Resistant
Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Bangladesh, China, India, Russia
China, Russia
Africa
Ethiopia, Kenya, Morocco, South Africa, Tanzania
-
Europe
Austria, France, Germany, Greece, Italy, Romania, Scotland, Spain, Switzerland
Austria, Italy, Portugal, United Kingdom
Others
-
-
Deposits in Western Continents
North America
USA
Canada, USA
South America
Bolivia, Chile, Colombia, Ecuador, Peru, Venezuela
Argentina, Bolivia, Ecuador
Deposits in Oceania Continent
Australia
New South Wales, New Zealand, Queensland, Victoria, Western Australia
-