Calcium carbonate latter is especially evident in day-to-day life of people who have hard water. Water in aquifers underground can be exposed to levels of CO much higher than atmospheric. As such water percolates through calcium carbonate rock, the CaCO dissolves according to the second trend. When that same water then emerges from the tap, in time it comes into equilibrium with CO levels in the air by outgassing its excess CO. The calcium carbonate becomes less soluble as a result and the excess precipitates as lime scale. This same process is responsible for the formation of stalactites and stalagmites in limestone
Resava Cave formed by the sinking river in the limestone substrate. Cave formations are right at the entry. They are formed through the dissolving of the calcium carbonate. The color depends on the mineral through which the water flows: red from the iron oxide, white from the crystallized calcium and yellow from the traces of clay. The symbol of the cave is a massive stalagmite, tall and wide. After its appearance, it was named the Statue of mother with a child. The cave consists of 8 halls. Resava cave was accidentally discovered by the local shepherds in 1962. After being explored for