Why can't I build extractors?

[[OO] coldsteel]

New player here. I have glasssteel and titanium resources just outside my starting region bounderies. I researched the alchemist's furnace which should allow me to build extractors for those resources but the extractors do not show up in the construction options and there's no flag on the resources. Does anyone know why? What am I missing here? Do resources have to be within the blue starting region boundary to build the extractor?

[Astasia]

Everything is tied to the region it's in. You need to build a city in that region to claim the territory and build the extractors there.

[Groo the one]

Exactly. You only can build extractors (and all other buildings) in regions you still did colonize. If your faction colour is blue, these are the blue regions.

[[OO] coldsteel]

Okay thanks.