The monolith facilities don't create anything, they just mine all three resources at once. They take a while to build, but are useful for domed colonies with limited space.
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Technological advancement is like an axe in the hands of a pathological criminal. --A. Einstein
Just like almost every other type of resource extractor, a monolith's "fixed number" is modified by the resource percentage as listed on the planet it has been built on. The only difference is that because monoliths generate all 3 resources, the 3 modifiers have to be applied separately to the same facility.
So no, you can't build a monolith 3s on a world with 0% minerals and expect to get minerals out of the deal.