This sound like Ghara https://en.wikipedia.org/wiki/Ghara which is very common in rural areas in subcontinent. It keeps water cool in summer. It gives water a very nice earthy taste. Ghara is usually paired with a clay bowl to drink water.

If you can buy a clay bowl or glass, get it and keep water in it on your side and drink from. It will be cool and will have a very nice earthy flavour. But not all clay pots are same quality. Some are not very porous and won't cool the water or give you different taste.