Well it depends on how much oil you have on your hands.. wash your hands before entering into the cave! haha... I'm joking... but yes...
the oil on your hands will stay on the stalagmites once you touch them, like small fingertips and oil repels water with the minerals so it prevents the minerals to stick there.

There are wonderful humans beings that are worried about touching them... and then there is this shit
Chinese tourist kicks down 10 million-year-old stalagmite:

a beautiful yellow flower... I will try not to touch them ;)
Beautiful post, well formatted too :)