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 /

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

See Examples For:

glauconite

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

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

The colouring matter is believed in every case to be glauconite.

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

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 J. Cecil Hughes

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