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 Bauxite is a complex mix of the minerals gibbsite, boehmite, and diaspore, formed as less stable minerals like feldspar and mica react with water. David Bressan, Forbes, 4 July 2021 The exact composition of porcelain varies depending on its use and the manufacturer, although one common ingredient is kaolin, a soft white clay that is combined with other ingredients like bone ash, sand, magnesium, quartz, and feldspar. Melissa Locker, Southern Living, 30 June 2021 The most common lava rock found at Mount St. Helens is indeed Dacite, composed predominantly of plagioclase feldspar and quartz (pure silicon-dioxide). David Bressan, Forbes, 18 May 2021 The sand reflects the rocky outcrops found inland and along the coast and is composed mostly of grains of quartz, feldspar, limestone and fragmented shells. David Bressan, Forbes, 27 Apr. 2021 Basalt is the most common rock on Earth, formed directly by crystallization of feldspar, pyroxen, olivine and quartz from a magma rich in iron and silica. David Bressan, Forbes, 10 Mar. 2021 Generations of Spruce Pine miners tossed the quartz aside in favor of the feldspar and mica. Sam Farmer, Los Angeles Times, 11 Nov. 2020 Later the region was mined for the feldspar in the granite ledges. courant.com, 12 Aug. 2019 The researchers examined zircon, an incredibly resilient mineral, as well as feldspar and quartz from the rock sample, according to Mike Wall at Space.com. Jay Bennett, Smithsonian, 28 Jan. 2019

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.

See More

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

Keep scrolling for more

Learn More About feldspar

Time Traveler for feldspar

Time Traveler

The first known use of feldspar was in 1772

See more words from the same year

Dictionary Entries Near feldspar




See More Nearby Entries 

Statistics for feldspar

Last Updated

20 Jul 2021

Cite this Entry

“Feldspar.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/feldspar. Accessed 19 Sep. 2021.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

Keep scrolling for more

More Definitions for feldspar



English Language Learners Definition of feldspar

: a very common type of mineral

More from Merriam-Webster on feldspar

Nglish: Translation of feldspar for Spanish Speakers

Britannica.com: Encyclopedia article about feldspar


Test Your Vocabulary

Farm Idioms Quiz

  • cow coming home
  • What does 'poke' refer to in the expression 'pig in a poke'?
Name That Thing

Test your visual vocabulary with our 10-question challenge!

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!