Definition of plagioclase
: a triclinic feldspar; especially : one having calcium or sodium in its composition
Recent Examples of plagioclase from the Web
Your average Hood plagioclase crystal that formed 21,000 years ago might have spent only 1-12% of its entire history, a few hundred to a few thousand years, in conditions that would have allowed eruption of the magma (think: hot).
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'plagioclase'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Learn More about plagioclase
Britannica.com: Encyclopedia article about plagioclase
Seen and Heard
What made you want to look up plagioclase? Please tell us where you read or heard it (including the quote, if possible).