Is the only place to get this through the completion of the terror of high halls mission or whatever mission that was? I gave them to the blind prophet and now I find out to use the best enchanments you need it so is there any place else to get some?
I found one in a chest in the derelict caves (chest appeared while standing on a pressure plate), I know they're rare but you can find them elsewhere.
Broken Valley (before destruction) - 3 gems
2 gems you can buy from Lamotte (village merchant)
1 gem you will get as reward from sleeping trio (wake them up)
Orobas Fjords - 13 gems
1 gem - read the Charlie's (goblin on the small island) mind and you will get a malachite in his chest
1 gem - random merchant on the road to High Halls (appears only once)
2 gems - two malachite's veins in Patriarch's cave
4 gems - after finishing second quest in High Hall (water supply), read the woman's mind (who gave you the quest)
1 gem - High Hall, second quest dungeon - check malachite vein in the same room where demon is (do it before you will transform into dragon)
1 gem - malachite vein in the cave of treasure quest (orobas fjords, four adventures looking for a treasure)
2 gem - Redcliff's quest, you can trade to goblins precious redcliff stone for 2 malachite gems
1 gem - malachite vein after a 3 pedestals with colored books