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Chalk is so common in Cretaceous marine beds that the Cretaceous Period was named for these deposits. The name Cretaceous was derived from Latin creta, meaning chalk. [10] Some deposits of chalk were formed after the Cretaceous. [11] The Chalk Group is a European stratigraphic unit deposited during the late Cretaceous Period.
The Chalk Group (often just called the Chalk) is the lithostratigraphic unit (a certain number of rock strata) which contains the Upper Cretaceous limestone succession in southern and eastern England. The same or similar rock sequences occur across the wider northwest European chalk 'province'.
The National Trust, which owns the surrounding areas, plans to return the land to a natural state of chalk grassland and preserve existing military structures from the Second World War. [35] In June 2021, a wildflower meadow on White Cliffs of Dover was named in honour of Dame Vera Lynn.
Chalk mining is the extraction of chalk from underground and above ground deposits by mining. [1] Mined chalk is used mostly to make cement and bricks . Chalk mining was widespread in Britain in the 19th century because of the large amount of construction underway (and the Industrial Revolution ). [ 2 ]
Limestone is commonly white to gray in color. Limestone that is unusually rich in organic matter can be almost black in color, while traces of iron or manganese can give limestone an off-white to yellow to red color. The density of limestone depends on its porosity, which varies from 0.1% for the densest limestone to 40% for chalk.
Chalk is a type of sedimentary rock, composed predominantly of calcium carbonate. Chalk may also refer to: The Chalk Group, a stratigraphic unit in northwest Europe. The Chalk country, a region of Discworld; Blackboard chalk and sidewalk chalk, a material used for writing and art, usually composed of calcium sulfate or calcium carbonate.
A piece of flint 9–10 cm (3.5–3.9 in) long, weighing 171 grams. Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, [1] [2] categorized as the variety of chert that occurs in chalk or marly limestone.
The name Crayola was suggested by Alice Binney, wife of company founder Edwin Binney, combining craie, French for "chalk," a reference to the pastels that preceded and lent their name to the first drawing crayons, with the suffix -ola, meaning "oleaginous," a reference to the wax from which the crayons were made. [1]