tufa
Porous calcium rock
Tufa is a porous limestone formed when calcium carbonate precipitates from spring water or streams.
It builds up in spongy, irregular masses around springs, lake edges, and waterfalls.
The rock is soft enough to cut into blocks, making it useful for garden walls and decorative stonework: tufa towers rising from the lake bed.
Not to be confused with tuff, volcanic ash that has solidified into rock.
Carbonate sedimentary rock
- travertineLimestone from thermal springs
- calcareousContainingite calcium carbonate chalk
- porousAllowing passage of fluids
- vesicularHaving small sacs
spongy · friable · lightweight · rough · honeycombed · cellular · permeable · soft rock
Mineral in shells and marble
- calciteCrystalline calcium carbonate
- aragoniteCalcium carbonate crystal form
- precipitateHeadlong and reckless
- alkalineHaving high pH
mineral deposit · effervescence · freshwater · spring water · supersaturated · bicarbonate · groundwater · marl
Hanging cave mineral deposit
- stalagmiteUpward-growing cave deposit
- dripstoneCave mineral deposit
- flowstoneCalcite sheet from seepage
- sinterHeat-fuse without liquefying
hot spring · terraces · biofilm · algae · cyanobacteria · encrustation · layered · banded
Heated groundwater emerging naturally
- karstEroded soluble rock terrain
- terracesRaised flat outdoor areas
- towersTall vertical structures
- pinnaclesHighest or culminating points
Tivoli · spires · mounds · scenic · geological wonder · natural monument · shoreline
Quarried rock for construction
- Roman concreteDurable ancient building mixture
- aquariumTank for keeping fish
- insulationThermal transfer prevention
- water gardenCultivated aquatic plant display
rockery · aggregate · masonry · sculptural · architectural
limestone
Carbonate sedimentary rock
- travertineLimestone from thermal springs
- calcareousContainingite calcium carbonate chalk
- porousAllowing passage of fluids
vesicular · spongy · friable · lightweight · rough · honeycombed · cellular · permeable · soft rock · buff
calcium carbonate
Mineral in shells and marble
- calciteCrystalline calcium carbonate
- aragoniteCalcium carbonate crystal form
- precipitateHeadlong and reckless
alkaline · mineral deposit · effervescence · freshwater · spring water · supersaturated · bicarbonate · groundwater · marl · hardness
stalactite
Hanging cave mineral deposit
- stalagmiteUpward-growing cave deposit
- dripstoneCave mineral deposit
- flowstoneCalcite sheet from seepage
sinter · hot spring · terraces · biofilm · algae · cyanobacteria · encrustation · layered · banded · accretion
hot springs
Heated groundwater emerging naturally
pinnacles · Tivoli · spires · mounds · scenic · geological wonder · natural monument · shoreline
building stone
Quarried rock for construction
- Roman concreteDurable ancient building mixture
- aquariumTank for keeping fish
- insulationThermal transfer prevention
water garden · rockery · aggregate · masonry · sculptural · architectural
- building stoneashlar, bluestone, brownstone, building stone, cobblestone
- CappadociaCappadocia, underground cities, cave dwellings, hot air balloons, rock formations
- geological formationsmineral deposit, ore deposit, coal deposit, oil deposit, gold deposit
- limestonecalcite, calcium carbite, chalk, dolomite, marl
- mineral depositslimestone, chalk, salt, gypsum, calcite
- rock gardensrock garden, rockeries, rockery, alpine garden, rocks
- welded tuffVolcanic rock from hot ash