Where is the Gold ore?

Forgive my ignorance since I've recently started the game (loving it so far!). Been trying to do the quests, but on my whole playthrough I came across a gold ore once, in the Cave Pit Fall at Goblin's Cave.

Saw some guides mentioning more in the Fortress but only Copper and Blue rock no matter where I go. Most guides are quite 6-12 months old so due to updates, they most likely got outdated. Same goes for the neat Dark and Darker Interactive Map from the wiki.

Also tried the higher gear grade mode but no luck. Are they more prone to appear on the high-roller map? If anyone knows more common areas please let me know!