Encyclopedia Britannica
Encyclopedia Britannica
SUBSCRIBE
SUBSCRIBE
  • Home
  • History & Society
  • Science & Tech
  • Biographies
  • Animals & Nature
  • Geography & Travel
  • Arts & Culture
  • ProCon
  • Money
  • Games & Quizzes
  • Videos
  • On This Day
  • One Good Fact
  • Dictionary
  • New Articles
History & Society
  • Lifestyles & Social Issues
  • Philosophy & Religion
  • Politics, Law & Government
  • World History
Science & Tech
  • Health & Medicine
  • Science
  • Technology
Biographies
  • Browse Biographies
Animals & Nature
  • Birds, Reptiles & Other Vertebrates
  • Bugs, Mollusks & Other Invertebrates
  • Environment
  • Fossils & Geologic Time
  • Mammals
  • Plants
Geography & Travel
  • Geography & Travel
Arts & Culture
  • Entertainment & Pop Culture
  • Literature
  • Sports & Recreation
  • Visual Arts
  • Companions
  • Demystified
  • Image Galleries
  • Lists
  • Podcasts
  • Spotlight
  • Summaries
  • Top Questions
  • #WTFact
  • Britannica Kids
Ask the Chatbot Games & Quizzes History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture ProCon Money Videos
groundmass
Directory
References
Discover
Middle East bee locator map
Are the Middle East and the Near East the Same Thing?
NBA Lakers Celtics Finals Kevin Garnett shooting.
10 Great Sports Rivalries
Time zone map with standard time zones and International Date Line
Why Are Some Time Zones 30 Minutes Off Instead of an Hour?
Close up of praying mantis walking on stone ground against a blurred background in Japan
6 Animals That Eat Their Mates
Paul Revere. "The bloody massacre perpetrated in King Street Boston on March 5th 1770 by a party of the 29th Regt.," engraved by Paul Revere. Boston Massacre.
There’s a Riot Goin’ On: Riots in U.S. History (Part One)
Demystified - Do Lemmings Really Commit Mass Suicide? illustration
Do Lemmings Really Commit Mass Suicide?
Estimated battle casualties, Normandy invasion, World War II. WWII, D-Day
Estimated Battle Casualties During the Normandy Invasion and Campaign to Liberate Paris (June–August 1944)

groundmass

geology

Learn about this topic in these articles:

relationship to matrix

  • Matrix
    In matrix

    …a crystalline rock, sometimes called groundmass.

    Read More