Have a good weight Argentavis (with a saddle, so you can craft behemoth gates) filled with thatch following your golem (on high range works the best) and get wood & stone with the elemental. Transfer the wood & stone you get into the Argentavis and make Behemoth gates. You can also just make other stone stuff, no need for argent but remember to bring thatch!
If you place a platform saddle on a parcer and make it have sloped ceilings going down to the ground on the side(s) you can then put rock golems on the ramps you can get infinite rocks/metal without having to worry about the weight limit on the parcer or the golem
The rock elemental is an amazing gatherer mostly for stone, but also gets some insane amounts of meat, and keeps it from getting spoiled for a good amount of time. Rock elementals also are one of the best defenses against dragons. The rock throw attack seeks the nearest target agains you to make the attack a little easier to make contact with target