Magic weapons, armor and shields costs

Imagine a +2 heavy steel shield.
Does it cost 4000gp? Or do I have to add the 170gp of the masterwork shield itself to that base price listed on the Amor & shields table (making it 4170)?.

I ask this because new Pathfinder rules seem to say that magic weapons, shields and armor are assumed to be masterwork without any extra cost (it wasn't so in 3.5 rules, where quick reference tables with masterwork items costs were provided).
Thanks :P

A weapon, shield or armor MUST be masterwork before becoming a magic item. So yes +2 full plate costs 5,650gp. It's stated under the creating magic items section.

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