Board Thread:Theories & Speculation/@comment-1512913-20141028151348/@comment-945885-20141101002938

The databook will have an entry for the technique that will specifically categorize it. Then the debate can end.

As for the Jinchuriki using advanced natures after extraction, Gaara is the only example we have and his father had Magnet Release to begin with. Gaara may have been left as a "pseudo Jinchuriki," retaining some of Shukaku's power, or he may be using Magnet Release on the sand somehow, despite it not being metal (Naruto's Magnet Release also used sand). As I recall, Gaara did mix blood (which contains iron) into his sand to strengthen it when he was still a sociopath.