Quinley

No, it's not a bug, it's just the system like that, as other jobs also required another Purified gems in their special skills. You will need to craft Purified Aquamarine by destructing Aquamarine into the pieces, then Construct the pieces using Purified Water. All items are available at Tasartia @Alker Harbor. For destructing and constructing, press 'S' then click the third tab (Action Tab).