plagioclase
noun
pla·gio·clase
ˈplā-j(ē-)ə-ˌklās 
ˈpla-,
-ˌklāz
: a triclinic feldspar
especially
: one having calcium or sodium in its composition
Examples of plagioclase in a Sentence
Recent Examples on the Web
Additionally, the meteorites both contain only trace amounts of the mineral plagioclase, which is thought to make up over 37 percent of Mercury’s surface.
—
Sara Hashemi, Smithsonian Magazine, 17 July 2025
Several apatite grains are observable in the margins of plagioclase and pyroxene (Supplementary Fig. 3).
—Keith Cooper, Space.com, 16 July 2025
However, the meteorites contained only trace amounts of plagioclase, a mineral believed to dominate Mercury’s surface.
—Jacopo Prisco, CNN Money, 14 July 2025
The countertop has quartz, plagioclase feldspar, potassium feldspar and biotite?
—Erik Klemetti, Discover Magazine, 25 Mar. 2025
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Sara Hashemi, Smithsonian Magazine, 17 July 2025
Several apatite grains are observable in the margins of plagioclase and pyroxene (Supplementary Fig. 3).
—Keith Cooper, Space.com, 16 July 2025
However, the meteorites contained only trace amounts of plagioclase, a mineral believed to dominate Mercury’s surface.
—Jacopo Prisco, CNN Money, 14 July 2025
The countertop has quartz, plagioclase feldspar, potassium feldspar and biotite?
—Erik Klemetti, Discover Magazine, 25 Mar. 2025
Cite this Entry
“Plagioclase.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/plagioclase. Accessed 10 Sep. 2025.
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