Economy in 5.2+

[Karst]

Platinum in numining is unviable if you can't export to Gallia, which almost none of the factions that can mine it can do.

Could you explain the platinum part?

The Promethene fuel recipe is unviable.

The promethene recipes are still horrible.

Could either or both of you explain the concern with it and I can possibly look at it later, I am largely unfamiliar with it.

Probably easier to explain in PM, but the short versions are:
For Platinum, it has a highly restrictive "luxury" buyers list that features extremely few destinations outside Gallia which makes it hard to connect, and none of which have csu that are particularly good. It barely competes with NPC HRCs like Optronics.

For Promethene, the fairly uncommon base ingredient, the two extremely exclusive minor ingredients, the lack of ingredients produced as byproduct (like Toxic Waste is), and the low base price of the end product make it unviable.
For example, you might reasonably expect that in Tau-23, just one jump from base price sources of two of the three ingredients, it would pay to make it, but it doesn't, not even for use, nevermind export. It's still cheaper to just buy fuel.
I think the processing ratio is what really needs to change; there's just no way a 2.2 : 1 recipe that produces a generic low value commodity is going to be worthwhile. It needs far greater output.

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