calcite

American  

[kal-sahyt] / ˈkæl saɪt /

noun

1. one of the commonest minerals, calcium carbonate, CaCO 3 , found in a great variety of crystalline forms: a major constituent of limestone, marble, and chalk; calc-spar.

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calcite British  

/ ˈkælsaɪt, kælˈsɪtɪk /

noun

1. a colourless or white mineral (occasionally tinged with impurities), found in sedimentary and metamorphic rocks, in veins, in limestone, and in stalagmites and stalactites. It is used in the manufacture of cement, plaster, paint, glass, and fertilizer. Composition: calcium carbonate. Formula: CaCO 3 . Crystal structure: hexagonal (rhombohedral)

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calcite Scientific  

/ kăl′sīt′ /

1. A usually white, clear, pale-yellow or blue orthorhombic mineral. Calcite occurs in many different forms and is the main component of chalk, limestone, and marble. It is a polymorph of aragonite. Chemical formula: CaCO ₃ .

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Other Word Forms

• calcitic
  adjective

Etymology

Origin of calcite

First recorded in 1840–50; calc- + -ite ¹

Compare meaning

How does calcite compare to similar and commonly confused words? Explore the most common comparisons:

• aragonite vs. calcite

Example Sentences

It was rediscovered in 2022 after decades of being overlooked by archaeologists, partially due to the calcite flow on top of it making the rock art difficult to see.

From BBC • Jun. 1, 2026

The article "U-Pb calcite age dating of fossil eggshell as an accurate deep time geochronometer" was published in Communications Earth & Environment.

From Science Daily • Dec. 21, 2025

“I was in the studio one day, working on this piece of honeycomb calcite, and I just went numb,” she recalls.

From Seattle Times • Feb. 23, 2024

Deciphering the chemical composition of each individual page—each thin, calcite layer—gives scientists a diary of the seawater through which the animal journeyed as it built its shell.

From National Geographic • Aug. 23, 2023

A variety of trap or basaltic rock, containing small cavities, occupied, wholly or in part, by nodules or geodes of different minerals, esp. agates, quartz, calcite, and the zeolites.

From Webster's Unabridged Dictionary by Webster, Noah