-Her: Jewel's a dude, although technically I'm not sure if that's even a physical thing with his race.
As to the whole using elementals, really depends on how you do it, his ties to other elementals, if there are two different kind of elementals being the primal and the sapient as I hazarded at before, how elementals view other elementals, how in-tune dwarfs are to elementals, etc. He certainly won't feel comfortable around you with the thought that you could force him into servitude if he finds out, that I can promise regardless of the above.
Also depends on if he's forced by your fault to go into said bloodrage, although I highly doubt such a thing would happen, Ross is the kind of guy who likes to keep player agency in their hands from what I've heard him say. Really, I know nothing about other elementals and Ross hasn't talked about them much so I can't rightly say anything. If Joe treats them badly, he certainly won't be happy and might act with force, either restraining wise or harmful depending, if you treat them too badly, but if Joe treats them nicely he'd probably ask if it's possible for Joe to ask instead of force them to do stuff. But really, he'd do the same if you were a slave-o-mancer or something. ...Which I suppose you are kinda, depending on how you do it and how its viewed. Man, bet necromancers are probably viewed similar with sapient undead running around.
It's all kinda wishy-washy really. I mean, I imagine when you went with Elementurgy you were imagining the barely relate-able beings in D&D, in Ross'verse I can confirm that dwarfs and dryads are elementals although as to if they act as per the norm that is another question. I mean, I imagine dwarfs are different enough from elementals considering that they have their own private language aside from the Elementure language, and Jewel was primarily raised by dwarfs, or at least more general earth elementals (instead of stone as dwarfs are) who lived with dwarfs.
I do think I should warn you that more things than giant rock formations, twisters, giant waves, and trails of fire will be after you with that trait though, who knows what else might be an elemental since in this 'verse I can hazard a guess that it can be of any type considering what Ross said about dwarfs being (stone) and dryads being (wood). ...Huh, wonder if there's a steel elemental. Ugh, or maybe something volatile, like uranium or plutonium. Scary thought.
EDIT: Er, sorry for drowning you in text. Don't know why, but this thread brings out my verbosity.