The latest official video from Blizzard revealed some of the upcoming changes to the costs of Masterworking. Blizzard has previously mentioned that they have increased the crafting costs now that Masterworking can no longer fail.
Masterworking Can No Longer Fail Masterworking Guide
These are the costs for various Masterworking ranks in comparison between the PTR and the upcoming Live version of Patch 1.4.0.
