Chert is a fine-grained silica-rich microcrystalline or cryptocrystalline sedimentary rock that may contain small fossils. source
Chert is a fine-grained silica-rich microcrystalline or cryptocrystalline sedimentary rock that may contain small fossils.
Chert varies greatly in color (from white to black). source
Chert varies greatly in color (from white to black).
Chert most often manifests as gray, brown, grayish brown and light green to rusty red. source
Chert most often manifests as gray, brown, grayish brown and light green to rusty red.
Chert s color is an expression of trace elements present in the rock. source
Chert s color is an expression of trace elements present in the rock.
Chert occurs as oval to irregular nodules in greensand, limestone, chalk, and dolostone formations as a replacement mineral. source
Chert occurs as oval to irregular nodules in greensand, limestone, chalk, and dolostone formations as a replacement mineral.
Chert also occurs in diatomaceous deposits and is known as diatomaceous chert. source
Chert also occurs in diatomaceous deposits and is known as diatomaceous chert.
Diatomaceous chert consists of beds and lenses of diatomite which were converted during diagenesis into dense, hard chert. source
Diatomaceous chert consists of beds and lenses of diatomite which were converted during diagenesis into dense, hard chert.
In petrology the term "chert" is used to refer generally to all rocks composed primarily of microcrystalline, cryptocrystalline and microfibrous quartz. source
In petrology the term "chert" is used to refer generally to all rocks composed primarily of microcrystalline, cryptocrystalline and microfibrous quartz.
Among petrologists, chalcedony is sometimes considered separately from chert due to its fibrous structure. source
Among petrologists, chalcedony is sometimes considered separately from chert due to its fibrous structure.
Cherts are subject to problems when used as concrete aggregates. source
Cherts are subject to problems when used as concrete aggregates.
In some areas, chert is ubiquitous as stream gravel and fieldstone and is currently used as construction material and road surfacing. source
In some areas, chert is ubiquitous as stream gravel and fieldstone and is currently used as construction material and road surfacing.
There are numerous varieties of chert, classified based on their visible, microscopic and physical characteristics. source
There are numerous varieties of chert, classified based on their visible, microscopic and physical characteristics.
Piatra Tomii, a prehistoric chert mine in Alba County, Romania source
Piatra Tomii, a prehistoric chert mine in Alba County, Romania
Magadi-type chert is a variety that forms from a sodium silicate precursor in highly alkaline lakes such as Lake Magadi in Kenya. source
Magadi-type chert is a variety that forms from a sodium silicate precursor in highly alkaline lakes such as Lake Magadi in Kenya.
In prehistoric times, chert was often used as a raw material for the construction of stone tools. source
In prehistoric times, chert was often used as a raw material for the construction of stone tools.
Chert has been used in late nineteenth-century and early twentieth-century headstones or grave markers in Tennessee and other regions. source
Chert has been used in late nineteenth-century and early twentieth-century headstones or grave markers in Tennessee and other regions.
