How to get more gold after Khrumbul-dun?

In Khrumbul-dun I got daily amounts of metal. This haul I took over to the Isle of Awakening. But as gold was the last one and I was going on with the story and they stopped bringing up metals for me.

How can I get easily gold now? Because mining it is kinda hard as the blocks are hard to break. Should I have waited longer to progress the story and get more days with mining hauls this way?