In the burning steppes you have elite dragonspawn and elite wymkrin. These are roughly lvl 55 56 elites that carry massive amounts of gold on them (about 30 silver each) They drop Great items.
I just 30 minutes of farming i made 26 gold. 4 Green Drops and the 2 to 30 silver they give. Doing this for about 3 hours will be great money. Also these dragons have a rare skin ( i forgot what there called) on every kill. These are bought by blacksmiths and enchanters for 20 gold EACH on my server . Diffrent servers may be more expensive or cheaper.

Its right u can get good money from those.

the thing they drop is Black dragonscale. And on my server (Doomhammer) they are only worth 1g pcs.

Yup. This is a very good money maker. And the Dragonkin respawn in roughly 1-2 mins.