Taaffeite, Painite & Co. Welcome! You are encouraged to register with the site and login (for free). When you register, you support the site and your question history is saved.Taaffeite costs more per ounce than painite. But since plutonium costs more per ounce than platinum, it follows that taaffeite costs more per ounce than platinum.Any of the following, if introduced into the argument as an additional premise, makes the argument above logically correct EXCEPT: Plutonium costs more per ounce than taaffeite. Taaffeite and plutonium cost the same per ounce. Painite and plutonium cost the same per ounce. Painite costs more per ounce than platinum. Painite costs more per ounce than plutonium. Review Answer