Something seems to have happened with the generation of ores in the procedurally generated realms - Zinc, Shimmering, Pursuit, and Aryium are the only ones that spawn regardless of realm difficulty or biome. The bunkers seem to have different gem and rare ore spawns based on the biome and difficulty, but I haven't seen ores such as Copper or Silver outside of the Storied Realms, which makes several recipes that require rare metals or Brass/Bronze obtainable only by replaying finished Storied Realms.
I'm having an inverse issue, I'm only seeing shimmering ore and some zinc spawn in my Ascended Astrolab realm, I wish I could get higher tier ores there. Maybe it's random? Or higher tiers are locked behind hidden checkpoints in the game? Either way it would be nice if all ores spawned in it, maybe have different sections of the map spawn different tiers of ore. As is I'll have to go gather in the story realms.
To the previous commenter - you can reset the story realms from the Crossways when inserting a new Major Realm Card, this will allow you to gather more copper.
I think it is almost a fatal bug that I can't get copper.
Since I cannot make brass, I cannot make many crafting platforms.
In the desert cave, there was ore that looked like copper, but I couldn't even check because the required mining power was 50. Copper before the rebuild should have been 40.
Even if I make a tier 3 pickaxe with only tier 3 materials, I can't do anything with barely 40 power.