feld·​spar | \ ˈfel(d)-ˌspär How to pronounce feldspar (audio) \

Definition of feldspar

: any of a group of crystalline minerals that consist of aluminum silicates with either potassium, sodium, calcium, or barium and that are an essential constituent of nearly all crystalline rocks

Examples of feldspar in a Sentence

Recent Examples on the Web

Connecticut has 304 identified mineral deposits, the most commonly listed are feldspar, iron, and mica. Courant Community, "Community News For The Windsor Locks Edition," 1 May 2018 One of those the-world-and-all-its-banks-are-mine skulls that looks like it’s made of feldspar and weighs a metric ton. Virginia Heffernan, WIRED, "Beware the Academic Vanity Honeypot," 30 Mar. 2018 Dating of quartz and feldspar grains provided estimates between approximately 62,000 and 85,000 years old, lining up neatly with the U-series dates. Cathleen O'grady, Ars Technica, "Humans were in Indonesia more than 63,000 years ago," 11 Aug. 2017 A new paper in Nature tries to quantify some of these questions by looking at the age and compositional data recorded in plagioclase feldspar crystals. Erik Klemetti, WIRED, "The Ephemeral Nature of Magma Prior to Eruption," 17 Feb. 2014

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'feldspar.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of feldspar

1772, in the meaning defined above

History and Etymology for feldspar

modification of obsolete German Feldspath (now Feldspat), from German Feld field + obsolete German Spath (now Spat) spar

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Time Traveler for feldspar

The first known use of feldspar was in 1772

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English Language Learners Definition of feldspar

: a very common type of mineral

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More from Merriam-Webster on feldspar

Rhyming Dictionary: Words that rhyme with feldspar

Spanish Central: Translation of feldspar

Nglish: Translation of feldspar for Spanish Speakers

Britannica.com: Encyclopedia article about feldspar

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