Are devils worth 7 blood each?

[Thufir]

The_Tauren13 said:
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I also think that astral pearls are worth more than water gems, so taking into account alchemy for payback time is somewhat lame. If anything, the clams have 8 or 9 turn payback because of relative gem worth.

The relative worth of astral vs. water is quite dependent on the nation, but IMO it's clear that for any clamhoarding nation (which is what we're talking about in this case), the water is worth more than the astral.

I expect that anybody that's doing clamhoarding (or at least doing it well) should be running a substantial surplus in astral, and doing a lot of alchemizing from astral to other types, never from non-astral to astral.