Diamonds can be found rarely with Ore in certain areas and they do drop from certain mobs, Here is a link to a wiki page with locations and the names of the bosses/mobs that drop them!
I know it may take awhile to start up some gardens, but that is the best way to keep a consistant flow of diamonds coming in.
You have some lower level wizards and they will need them if they are doing the crafting quests. Personally I like King Parsley. It drops aether, sunstone, black pearl, aquamarine, springs, diamonds, and amber. If you craft any of the loremaster spells that supply of amber helps.
Dragonspyre has several foes that drop them and you could probably do the battles/farming fast with your higher level wizards.
Ah so i know a simple solution on of the early areas of grizzleheim the second area i think its called mirkholm keep but on the left side there is like a grass route to the outside of the wolf camp if you walk around the edges there and do the switch realm tactic you can harvest about 70 ore half hour time this helped me with my dragonspyre crafting quests.
Valkoor NightTheif
Noah Night theif
