Board Thread:New on Marvel Cinematic Universe Wiki/@comment-1509585-20140804183803/@comment-25124692-20141031003942

Actually the teaser trailer says a lot. If it is not a primary stone it is directly related to the Tesseract and obviously plays a major part in relation to the other stones otherwise it wouldn't have been displayed so prominently in the teaser trailer DIRECTLY in the middle of showing and narrating about the other stones. No it has not been confirmed as a stone but it is implied that it has some sort of relation to the Stones in general.