glauconite

American  

[glaw-kuh-nahyt] / ˈglɔ kəˌnaɪt /

noun

1. a greenish micaceous mineral consisting essentially of a hydrous silicate of potassium, aluminum, and iron and occurring in greensand, clays, etc.

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glauconite British  

/ ˈɡlɔːkəˌnaɪt, ˌɡlɔːkəˈnɪtɪk /

noun

1. a green mineral consisting of the hydrated silicate of iron, potassium, aluminium, and magnesium: found in greensand and other similar rocks. Formula: (K,Na,Ca) 0.5-1 (Fe,Al,Mg) 2 (Si,Al) 4 O 10 (OH) 2 .nH 2 O

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Other Word Forms

• glauconitic
  adjective

Etymology

Origin of glauconite

1830–40; < Greek glaukón, neuter of glaukós ( see glauco-) + -ite ¹

Example Sentences

Less than a half-hour from Philadelphia, the Edelman, which opened March 29, takes full advantage of its site, once a sea teeming with marine creatures and, more recently, a glauconite quarry.

From The Wall Street Journal • Apr. 2, 2025

Similar bodies are found in the lower part of the Siluro-Cambrian, in the Quebec group at Point Levis; and there they are filled with a species of glauconite constituting a sort of greensand rock.

From The Chain of Life in Geological Time A Sketch of the Origin and Succession of Animals and Plants by Dawson, Sir J. William

It has been suggested that certain deposits of iron ores may owe their origin to deposits of glauconite, as for example those of the Mesabi range, Minnesota, U.S.A.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 1 "Gichtel, Johann" to "Glory" by Various

The green colour, on close inspection, is seen to be due to the presence of innumerable small green grains of a mineral called glauconite.

From Sea-Weeds, Shells and Fossils by Gray, Peter

They are made of a mixture of sand and clay coloured dark green by a mineral called glauconite.

From The Geological Story of the Isle of Wight by Hughes, J. Cecil