User blog comment:Mckrongs/Monster Hunter 4 for the Nintendo 3DS/@comment-5043481-20131105133938/@comment-22748142-20131107104841

Sorry for being late ,

That duplication only duplicate common gatherable low rank item, something like monster dung , fire sac , mushroom , etc.

You will need the item you want to duplicate and those crystalized feral wyvern virus ( the purple stone thinggy you get for defeat infected monster and Goa /Shagaru magara )

Unfortunately, you can 't duplicate monster material or potion , so this service is almost useless.