Definition

1. Noun:
   • A hard volcanic rock: A type of rock formed from compacted volcanic ash ejected during an eruption.
   • A soft porous limestone: A light, porous rock composed of calcium carbonate, deposited by mineral springs or groundwater.

Examples

• Noun:
  • The ancient city was built from blocks of tufa, which were easy to carve.
  • The hot springs have left behind extensive deposits of porous tufa.

Advanced Usage

• "Tufa cave": A cave formed within or from tufa deposits.
  • The area is known for its unique tufa caves and formations.
• "Tufa tower": A spire-like formation of tufa, often found in lakes.
  • Mono Lake in California is famous for its eerie tufa towers.

Variants and Related Words

• Tuff (n): A synonym specifically for the hard volcanic rock type of tufa.
  • The cliffs are composed of a durable tuff.
• Travertine (n): A form of limestone similar to the calcareous type of tufa, often used as building stone.
  • The famous Roman aqueducts were constructed using travertine.

Synonyms

• Volcanic tuff: For the hard, compacted ash rock.
• Calcareous sinter: For the soft, porous limestone deposited by springs.

Related Phrases

• Tufa deposition: The process by which calcareous tufa is formed.
  • Tufa deposition is accelerated in areas with high water flow and mineral content.

Noun

1. hard volcanic rock composed of compacted volcanic ash
2. a soft porous rock consisting of calcium carbonate deposited from springs rich in lime