tufa
tooh fuh
- n a soft porous rock consisting of calcium carbonate deposited from springs rich in lime
- n hard volcanic rock composed of compacted volcanic ash
- The base of the Palace will be marble and granite; the rest, tufa, a purple-red volcanic stone found in the Caucasus.
- The tufa towers produced by geological turmoil under the surface still stand, gnarled spires made of a material that Mark Twain likened to "inferior mortar dried hard": here a .
- Fantastical that landscape is, the tufa towers riddled with painted churches, like the sandcastles of giants' children, and I was amazed by it; but amazement is pretty soon .