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

The green grains which are so abundant in several minor subdivisions of the Cretaceous, are also in many instances really casts in glauconite of the chambered shells of these minute organisms.

From The Ancient Life History of the Earth A Comprehensive Outline of the Principles and Leading Facts of Palæontological Science by Nicholson, Henry Alleyne

Calcareous sands or impure limestones with glauconite are also by no means rare, an example being the well-known Kentish Rag.

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

In a few places a red colour prevails, the iron being mostly oxidized; elsewhere the muds are green owing to abundant glauconite.

From Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 4 "Cincinnatus" to "Cleruchy" by Various

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