In ark mobile . you can’t tame Rock Elementals in Genesis Part 1 The taming bar doesn’t appear
Rock Elemental
The Rock Elemental is a massive rock monster that is typically found disguised as a stone formation. When a survivor enters its territory, it will begin thrashing and throwing large boulders. Once tamed, it can be a highly effective siege weapon to bring into battle.

How ARK players tame and knock out the Rock Elemental: what to feed it, what to knock it out with, and how to keep it safe.