perlite

A gardener mixes perlite into potting soil.

Definition

1. Noun:
   • A volcanic glass: "Perlite" is a naturally occurring, amorphous volcanic glass that has a relatively high water content. It is typically gray or white and expands significantly when heated, forming a lightweight, porous material.

Usage Examples

• Noun:
  • Perlite is commonly used in horticulture to improve soil aeration and drainage. (The volcanic glass is added to soil for plant growth.)
  • The construction industry uses expanded perlite as an insulating material in walls and ceilings. (The heated, expanded form of perlite serves as insulation.)

Advanced Usage

• "Expanded perlite": perlite that has been heated to 800–1200°C, causing it to pop like popcorn and increase in volume up to 20 times.

  • Expanded perlite is lightweight and fire-resistant, making it ideal for industrial applications. (The processed material has enhanced properties.)

• "Crude perlite": the raw, unprocessed volcanic glass before expansion.

  • Crude perlite is mined and then crushed before being heated. (The untreated form of the mineral.)

Variants and Related Words

• Perlitic (adj): relating to or resembling perlite.
  • The perlitic texture of the rock indicates its volcanic origin. (The rock has a structure similar to perlite.)

Synonyms

• Volcanic glass: a broader term for glassy rocks formed from lava, including perlite.
• Pumice: a similar lightweight volcanic rock, though pumice is more vesicular (full of holes) than perlite.

Phrasal Verbs

• (None common for this technical term.)

Related Idioms

• (None common; perlite is a technical term without idiomatic usage.)