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

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

The term was introduced by the early English geologists for certain sandy rocks which frequently exhibited a greenish colour on account of the presence of minute grains of the green mineral glauconite.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 5 "Greek Law" to "Ground-Squirrel" by Various

The Hythe beds are interstratified thin limestones and sandstones; the former are bluish-grey in colour, compact and hard, with a certain amount of quartz and glauconite.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 5 "Greek Law" to "Ground-Squirrel" by Various

In a small number of Tertiary and older rocks glauconite occurs as an essential component.

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

The sandstones are grey in colour, weathering buff or reddish-brown, tinged more or less green by grains of glauconite.

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