If I recall correctly, the other resource was salt. I could be wrong. No specials, sadly. Sentinel level is few.

Lovely. What are the primary resources?
Well, the first 3 are going to probaly be Star Bulb / Copper / Parfinium.
What is the wild card?

Cobalt and Sodium are, IMHO, less useful than Salt or Magnetized Ferrite, or 'other'. Because, well, caves. Cobalt and Sodium.
Although, extractor farming Cobalt can be a lot of money early, for modest effort.

Are there any 'specials'? Salvageable Scrap or Ancient Bones?
Sentinel level?

The most Earth-like set up I've seen, great shot!