vermiculite

Definitions

Agriculture

  • noun a substance that is a form of silica processed into small pieces. It is used instead of soil in horticulture because it retains moisture.

Construction

  • A group name for certain clay minerals, hydrous silicates or aluminum, magnesium, and iron that have been expanded by heat. Vermiculite is used for lightweight aggregate in concrete and as a loose fill for thermal insulating applications.
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