Equip your Doedicurus with a saddle, pick it up with an Argentavis and fly near rocks as it automatically harvests the stone as you fly. Level up the melee damage to harvest more stone with each swing. Level up your Argentavis’ weight capacity be an insane stone harvest team.
Earlier I was on ARK Mobile. I have a massive wall around my base so my creatures can walk around in it. I went to my Doedicurus to put a saddle on it when I discovered it had almost 1300 stone in its inventory. Doedicurus when wandering autonomously destroy rocks to collect stones.
One cool think I found out is if you carry a tamed one with your Argy, hover over rocks and it will gather stone while being carried.. A damn hovering bulldozer💪.. (oh, same goes for Castroides and wood)