Definition
Oolite is a sedimentary rock formed from ooids, spherical grains which are composed of concentric layers of calcite
Chert is a hard, dark, opaque sedimentary rock which is composed of silica with an amorphous fine-grained texture
Discoverer
William Smith
Unknown
Etymology
From oo- + -lite, after German Oolit. A rock consisting of fine grains of carbonate of lime
From flint-like quartz, 1670s, of unknown origin- a local term, which has been taken into geological use
Class
Sedimentary Rocks
Sedimentary Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Hard Rock
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic or Non-Clastic
Banded, Rough
Color
Black, Blue, Brown, Cream, Green, Grey, Pink, Red, Silver, White, Yellow
Black, Brown, Green, Grey, Red, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Rounded and Rough
Glassy or Pearly
Interior Uses
Decorative Aggregates, Flooring, Interior Decoration
Decorative Aggregates, Homes
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Office Buildings
Other Architectural Uses
-
Curbing
Construction Industry
Cement Manufacture, Cobblestones, Landscaping
Arrowheads, Construction Aggregate, Cutting Tool, Spear Points
Antiquity Uses
Artifacts
Artifacts, Monuments
Commercial Uses
Creating Artwork, Jewelry, Used in aquariums
Creating Artwork, Gemstone, In fire-starting tools, Jewelry, To ignite fire, Used in flintlock firearms
Types
Pisolitic Oolite and Oncolitic Oolite
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Features
Available in lots of colors, Generally rough to touch, Very fine grained rock
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate
Archaeological Significance
Formation
Oolites form when layers of calcite are deposited around a sand grain or fossil piece and are rolled around in calm water, which makes them round.
Chert forms when microcrystals of silicon dioxide grow within soft sediments that become limestone or chalk. The chert formation can be either of chemical or biological origin.
Mineral Content
Calcite, Chert, Clay, Dolomite, Quartz, Sand, Silt
Quartz, Silicon
Compound Content
Aluminium Oxide, Ca, NaCl, CaO, Iron(III) Oxide, FeO, MgO
Silicon Dioxide
Types of Metamorphism
-
-
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion
Chemical Erosion
Grain Size
Fine Grained
Very fine-grained
Fracture
Conchoidal
Uneven, Splintery or Conchoidal
Porosity
Less Porous
Highly Porous
Luster
Pearly to Shiny
Waxy and Dull
Specific Gravity
-9999
2.5-2.8
Transparency
Opaque
Translucent to Opaque
Density
-9999 g/cm3
2.7 g/cm3
Resistance
Heat Resistant, Wear Resistant
Heat Resistant, Impact Resistant, Pressure Resistant, Wear Resistant
Deposits in Eastern Continents
Asia
Brunei, India, Indonesia, Malaysia, Singapore, Thailand, Vietnam
China, India, Iran, Japan, Oman, Russia, Saudi Arabia, Taiwan, Thailand, Vietnam
Africa
Cameroon, Chad, Ghana, Kenya, Malawi, Sudan, Tanzania, Togo, Zambia, Zimbabwe
Kenya, Morocco, South Africa, Tanzania
Europe
United Kingdom
Austria, France, Greece, Italy, Malta, Poland, Portugal, Serbia, Spain, Sweden, United Kingdom
Others
-
Greenland, Mid-Atlantic Ridge
Deposits in Western Continents
North America
USA
Canada, Mexico, USA
South America
Colombia
Bolivia, Brazil
Deposits in Oceania Continent
Australia
Adelaide, New Zealand, Queensland, Victoria, Yorke Peninsula
New South Wales, Queensland, South Australia, Western Australia
All about Oolite and Chert Properties
Know all about Oolite and Chert properties here. All properties of rocks are important as they define the type of rock and its application. Oolite and Chert belong to Sedimentary Rocks.Texture of Oolite is Clastic or Non-Clastic whereas that of Chert is Banded, Rough. Oolite appears Rounded and Rough and Chert appears Glassy or Pearly. The luster of Oolite is pearly to shiny while that of Chert is waxy and dull. Oolite and Chert are available in black, blue, brown, cream, green, grey, pink, red, silver, white, yellow colors. The commercial uses of Oolite are creating artwork, jewelry, used in aquariums and that of Chert are creating artwork, gemstone, in fire-starting tools, jewelry, to ignite fire, used in flintlock firearms.