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  • Boulders are the largest category of sediment particles, with a diameter greater than 256 millimeters. Compare with sand and pebbles.
  • Boulders can range in size from a few tens of centimeters to several meters in diameter.
  • They are typically found in areas of significant geological activity, such as glacial moraines, river valleys, and areas affected by landslides.
  • Boulders can be composed of various rock types, including granite, limestone, and basalt.
  • Due to their large size, boulders play a role in shaping landscapes, such as forming obstacles in rivers or creating distinctive landforms.
  • In construction and landscaping, boulders can be used as decorative elements or as structural features.